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  • 101.
    Bjorklund, Robert
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Filippini, Daniel
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Automatic optimization of experimental conditions for fast evaluation of diagnostic tests using ubiquitous instrumentation2008In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 134, no 1, p. 199-205Article in journal (Refereed)
    Abstract [en]

    Rapid quantitative determinations of creatinine, potassium and glucose, all important parameters in routine medical diagnostics, are demonstrated using a computer screen photo-assisted technique (CSPT). CSPT uses regular computer screens as light sources and web cameras as imaging detectors for supporting optical evaluations of diverse character. The ubiquity and versatility of the setup, makes CSPT an attractive candidate for point of care determinations. A robust procedure for the automatic selection of experimental conditions in CSPT evaluation, including camera channels and illuminating colors that minimize the measuring time up to 5 times is described. The method utilizes the correlation between experimental conditions and classification scores, obtained under a generic 50 color training session, to extract measuring sequences as short as 9 s. The extracted measuring conditions automatically adapted to the different tests provided a general, practical and fast approach for CSPT optimization in real scenarios. © 2008 Elsevier B.V. All rights reserved.

  • 102.
    Bjorklund, Robert
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Filippini, Daniel
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Generation of illuminating sequences for the computer screen photo-assisted evaluation of creatinine2006Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Poster på konferensen " Eurosensors XX, Göteborg, Sweden, 17-20 sept.

  • 103.
    Bjorklund, Robert
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Karlsson, Susanne
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Borén, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Analytical Chemistry .
    Allard, E
    Linkoping Univ, Dept Phys & Measurement Technol, S-58183 Linkoping, Sweden Linkoping Univ, Dept Water & Environm Studies, S-58183 Linkoping, Sweden.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Photodesorption of fulvic acid from iron oxide surfaces into aqueous solutions2001In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 174, no 2, p. 166-175Article in journal (Refereed)
    Abstract [en]

    Photodesorption of thin films of fulvic acid adsorbed on planar iron oxide surfaces was monitored by ellipsometry. Description was first observed at 546 nm, and additional fractions of the adsorbed acid left the surfaces at 405 and 365 nm Similar kinetics for photodesorption was observed from metallic iron films and from porous iron oxide prepared electrochemically by deposition on porous silicon substrates. Soluble photoproducts leaving the surface H ere monitored by UV absorbance spectroscopy at 200 nm Gaseous products were not detected by mass spectrometry but the results seemed to indicate that net all of the photoproducts entered the liquid phase. Of the metal films tested which adsorbed fulvic acid from aqueous solution (Fe. Cr, Ni, Al, and Pt), it was only iron which exhibited a photodesorption effect. (C) 2001 Elsevier Science B.V. All rights reserved.

  • 104.
    Bjorklund, Robert
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Louthander, Dan
    Senset AB, Linkoping.
    Martensson, Per
    Senset AB, Linkoping.
    Andersson, Staffan
    Billerud Skarblacka AB, Skarblacka.
    Kvist, Erland
    Billerud Skarblacka AB, Skarblacka.
    Ohrn, Margareta
    Billerud Skarblacka AB, Skarblacka.
    Krantz-Rülcker, Tina
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Online monitoring of inorganic cooking chemicals in white liquor by pulse voltammetry2010In: TAPPI JOURNAL, ISSN 0734-1415, Vol. 9, no 8, p. 49-53Article in journal (Refereed)
    Abstract [en]

    White liquor parameters in the recovery area of a kraft pulp mill were monitored for a 1-year period using rhodium as an electrode material in a sensor system based on pulse voltammetry. Shift personnel performed offline titration analysis of the liquor every 4 hours. The results for effective alkali, sulfidity, and total titratable alkali were used to train and validate the sensor for online monitoring. Partial least square regression models developed from 150 reference titration results for each parameter from the first month of the study predicted concentrations for the following 11 months. Validation of the models using titration results indicated that overall relative root mean squared errors for prediction of the parameters were 3.7% for effective alkali, 3.4% for sulfidity, and 5.1% for total titratable alkali. Process stops that exposed the sensor to temperature excursions or acid washings resulted in temporary periods of poor prediction.

  • 105.
    Bjorklund, Robert
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Magnusson, C.
    Arla Foods.
    Martensson, P.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Krantz-Rülcher , Christina
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Continuous monitoring of yoghurt fermentation using a noble metal electrode array2009In: International Journal of Food Science and Technology, ISSN 0950-5423, Vol. 44, no 3, p. 635-640Article in journal (Refereed)
    Abstract [en]

    An electrochemical probe containing gold, platinum and rhodium working electrodes was used to monitor yoghurt production in a pilot facility. Three commercial starting cultures at 40, 42 and 44 C transformed milk having 1.5% fat content to mild yoghurt products. The electrochemical changes in the broth during fermentation were recorded as current responses from pulse voltammetry over the electrodes. Principal component analysis of the responses generated two-dimensional score plots describing the qualitative fermentation progressions. Two distinct fermentation pathways were observed leading to similar final products. The pH was recorded during the fermentations and the data was used as reference values for creating a partial least squares model for prediction of pH as an example of a quantitative application for the sensor. The relative mean squared error for validation of the model using four probes interchangeably was about 2%. The probe was constructed of materials approved for use in the food industry and did not require a standard glass reference electrode.

  • 106.
    Bjorklund, Robert
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    W. Grant, Ann
    Volvo Technology, Göteborg.
    Jozsa, Peter
    Volvo Technology, Göteborg.
    Johansson, Mats
    VOLVO Cars Cororation, Göteborg.
    Fägerman, Per-Erik
    Mandalon Technologies, Linköping.
    Paaso, Jaska
    Selmic Oy, Oulu, Finland.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Hammarlund, Lars
    SenSiC AB, Stockholm.
    Larsson, Andreas
    SINTEF, Oslo, Norway.
    Popovici, Eveline
    University of Iasi, Romania.
    Lutic, Doina
    University of Iasi, Romania.
    Pagel, Joakim
    Lund University, Institutionen för designvetenskaper.
    Sanati, Mehri
    Lund University, Institutionen för designvetenskaper.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Soot sensor based on thermophoresis for high sensitive soot detection in diesel exhausts2010In: IMCS13, 2010, p. 250-Conference paper (Refereed)
  • 107.
    Björefors, Fredrik
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Ekeroth, Johan
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Borgh, Annika
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Konradsson, Peter
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Organic Chemistry .
    Electrochemical Analysis of Self-Assembled Monolayers2001In: Analysdagarna,2001, 2001Conference paper (Refereed)
  • 108.
    Bohme, O
    et al.
    Tech Univ Cottbus, D-03044 Cottbus, Germany Linkoping Univ, Swedish Sensor Ctr, S-58183 Linkoping, Sweden.
    Lloyd-Spets, Anita
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Schmeisser, D
    Tech Univ Cottbus, D-03044 Cottbus, Germany Linkoping Univ, Swedish Sensor Ctr, S-58183 Linkoping, Sweden.
    Nanoparticles as the active element of high-temperature metal-insulator-silicon carbide gas sensors2001In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 13, no 8, p. 597-+Article in journal (Refereed)
    Abstract [en]

    The sensor performance of MISiC (metal-insulator-silicon carbide) diode devices depends on their temperature pretreatment: an activation step at 600 degreesC leads to fast-responding devices with extraordinarily high signals but the devices fail when operated above 700 degreesC. The authors focus on the key role of nanoparticles in high-temperature gas sensor applications of these MISiC devices, presenting a model in which the interface dipole moment of nanoparticles is seen as the driving force and explaining the difference in response of capacitor-configuration and Schottky-diode-configuration devices.

  • 109.
    Briand, D.
    et al.
    Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland.
    Sundgren, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Van, Der Schoot B.
    Van Der Schoot, B., Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    De, Rooij N.F.
    De Rooij, N.F., Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland.
    Thermally isolated MOSFET for gas sending application2001In: IEEE Electron Device Letters, ISSN 0741-3106, E-ISSN 1558-0563, Vol. 22, no 1, p. 11-13Article in journal (Refereed)
    Abstract [en]

    This work reports on thermally isolated electronic components for gas sensing applications. The device is composed of an array of 4 MOSFET, a diode and a semiconductor resistor integrated on a micro-hotplate, which is fabricated using bulk micromachining of silicon. The thermal efficiency of the device is 2°C/mW with a thermal constant less than 100 ms. Holes are made in the passivation film over the gates of the MOSFET and gas sensitive films deposited on top of the gate insulator. The low thermal mass device realized allows new modes of operation for MOSFET gas sensors such as a combination of the field and thermal effects and a pulsed temperature mode of operation.

  • 110.
    Briand, D.
    et al.
    Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland, Actuators and Microsystems Lab., Institute of Microtechnology, Neuchâtel, Switzerland.
    Van, Der Schoot B.
    Van Der Schoot, B., Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland.
    De, Rooij N.F.
    De Rooij, N.F., Institute of Microtechnology, University of Neuchâtel, CH-2007 Neuchâtel, Switzerland, Research and Development Department, Cordis Europa N.V., Roden, Netherlands, Institute of Microtechnology, University of Neuchâtel, Neuchâtel, Switzerland.
    Sundgren, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Low-power micromachined MOSFET gas sensor2000In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 9, no 3, p. 303-308Article in journal (Refereed)
    Abstract [en]

    This paper reports on the design, fabrication, and characterization of the first low-power consumption MOSFET gas sensor. The novel MOSFET array gas sensor has been fabricated using anisotropic bulk silicon micromachining. A heating resistor, a diode used as temperature sensor, and four MOSFETs are located in a silicon island suspended by a dielectric membrane. The membrane has a low thermal conductivity coefficient and, therefore, thermally isolates the electronic components from the chip frame. This low thermal mass device allows the reduction of the power consumption to a value of 90 mW for an array of four MOSFETs at an operating temperature of 170 °C. Three of the MOSFETs have their gate covered with thin catalytic metals and are used as gas sensors. The fourth one has a standard gate covered with nitride and could act as a reference. The sensor was tested under different gaseous atmospheres and has shown good gas sensitivities to hydrogen and ammonia. The low-power MOSFET array gas sensor presented is suitable for applications in portable gas sensor instruments, electronic noses, and automobiles.

  • 111.
    Briand, D.
    et al.
    Institute of Microtechnology, University of Neuchâtel, P.O. Box 3, CH-2007 Neuchâtel, Switzerland.
    Wingbrant, Helena
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Sundgren, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Van, der Schoot B.
    Van der Schoot, B., Institute of Microtechnology, University of Neuchâtel, P.O. Box 3, CH-2007 Neuchâtel, Switzerland.
    Ekedahl, Lars-Gunnar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    De, Rooij N.F.
    De Rooij, N.F., Institute of Microtechnology, University of Neuchâtel, P.O. Box 3, CH-2007 Neuchâtel, Switzerland.
    Modulated operating temperature for MOSFET gas sensors: Hydrogen recovery time reduction and gas discrimination2003In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 93, no 1-3, p. 276-285Conference paper (Other academic)
    Abstract [en]

    This communication presents a modulated mode of operation for MOSFET gas sensors. A low-power micromachined device allows pulsing the temperature of MOSFET gas sensors with a time constant less than 100ms. Modulating the temperature during the gas exposure modifies the kinetics of the gas reactions with the sensing film. The way the sensor response is modified by the temperature modulation depends on the sensor "history", on the nature of the surrounding gaseous atmosphere, and on the type of materials used as catalytic sensing film. Pulsing the temperature up just after the gas exposure can reduce the recovery time for specific applications, such as for hydrogen detection. Cycling the temperature can allow the discrimination between different gas mixtures. Discrimination was shown for gaseous mixtures of hydrogen and ammonia in air. The results obtained indicate that a "smart" combination of sample and temperature profile could be used to expand the information content in the sensor response. © 2003 Elsevier Science B.V. All rights reserved.

  • 112.
    Bricarello, Daniel A
    et al.
    University of California, Davis, USA .
    Patel, Mira A
    University of California, Davis, USA .
    Parikh, Atul Navinchandra
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Inhibiting host-pathogen interactions using membrane-based nanostructures2012In: Trends in Biotechnology, ISSN 0167-7799, E-ISSN 1879-3096, Vol. 30, no 6, p. 323-330Article, review/survey (Refereed)
    Abstract [en]

    Virulent strains of bacteria and viruses recognize host cells by their plasma membrane receptors and often exploit the native translocation machinery to invade the cell. A promising therapeutic concept for early interruption of pathogen infection is to subvert this pathogenic trickery using exogenously introduced decoys that present high-affinity mimics of cellular receptors. This review highlights emerging applications of molecularly engineered lipid-bilayer-based nanostructures, namely (i) functionalized liposomes, (ii) supported colloidal bilayers or protocells and (Hi) reconstituted lipoproteins, which display functional cellular receptors in optimized conformational and aggregative states. These decoys outcompete host cell receptors by preferentially binding to and neutralizing virulence factors of both bacteria and viruses, thereby promising a new approach to antipathogenic therapy.

  • 113.
    Brunette, Donald M,
    et al.
    Faculty of Dentistry University of British Columbia, Vancouver, Canada.
    Tengvall, Pentti
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Textor, Marcus
    Dept. of Materials Swiss Federal Inst. of Technology, Zurich, Switzerland.
    Thomsen, Peter
    Inst. of Anatomy Cell Biology Göteborgs universitet.
    Titanium in Medicine: material science, surface science, engineering, biological responses and medical applications2001Book (Other academic)
    Abstract [en]

       This comprehensive book provides state-of-the-art scientific and technical information in a clear format and consistent structure making it suitable for formal course work or self-instruction. The authors are drawn not only from academic institutions but also from industry, so that practical aspects of implant fabrication and material handling are covered that are often lacking in biomaterials texts. Besides readers with a general interest in biomaterials, the book will interest materials investigators, surgeons and dentists using titanium implants, medical scientists and engineers, as well as lecturers at universities or institutes who would benefit by having ready access to authoritative information on the use of titanium for implants, devices and instruments. More information: http://www.titaniuminmedicine.com.

  • 114.
    Buchholt, Kristina
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Nanostructured materials for gas sensing applications2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this Thesis I have investigated the use of nanostructured films as sensing and contact layers for field effect gas sensors in order to achieve high sensitivity, selectivity, and long term stability of the devices in corrosive environments at elevated temperatures. Electrochemically synthesized Pd and Au nanoparticles deposited as sensing layers on capacitive field effect devices were found to give a significant response to NOx with small, or no responses to H2, NH3, and C3H6. Pt nanoparticles incorporated in a TiC matrix are catalytically active, but the agglomeration and migration of the Pt particles towards the substrate surface reduces the activity of the sensing layer. Magnetron sputtered epitaxial films from the Ti-Si-C and the Ti-Ge-C systems were grown on 4H-SiC substrates in order to explore their potential as high temperature stable ohmic contact materials to SiC based field effect gas sensors. Ti3SiC2 thin films deposited on 4H-SiC substrates were found to yield ohmic contacts to n-type SiC after a high temperature rapid thermal anneal at 950 ºC. Investigations on the growth mode of Ti3SiC2 thin films with varying Si content on 4H-SiC substrates showed the growth to be lateral step-flow with the propagation of steps with a height as small as half a unit cell. The amount of Si present during deposition leads to differences in surface faceting of the films and Si-supersaturation conditions gives growth of Ti3SiC2 films with the presence of TiSi2 crystallites. Current-voltage measurements of the as-deposited Ti3GeC2 films indicate that this material is also a promising candidate for achieving long term stable contact layers to 4H-SiC for operation at elevated temperatures in corrosive environments. Further investigations into the Ti-Ge-C system showed that the previously unreported solid solutions of (Ti,V)2GeC, (Ti,V)3GeC2 and (Ti,V)4GeC3 can be synthesized, and it was found that the growth of these films is affected by the nature of the substrate.

    List of papers
    1. Au Nanoparticles as Gate Material for NOx Field Effect Capacitive Sensors
    Open this publication in new window or tab >>Au Nanoparticles as Gate Material for NOx Field Effect Capacitive Sensors
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    2008 (English)In: Sensor letters, ISSN 1546-198X, Vol. 6, no 4, p. 577-584Article in journal (Refereed) Published
    Abstract [en]

    Gold nanoparticles (Au-NPs) are electrochemically synthesized in the presence of tetra-alkylammonium stabilizers and used as active element in Field Effect capacitive gas sensors. Before use, the sensing area is treated by a relatively mild annealing procedure aimed to partially remove the organic stabilizer without loosing the nano-structured character of the particles. Both pristine and annealed materials have been subjected to a spectroscopic and morphological characterization (by means of UV-Vis, XPS, TEM, SEM techniques). Preliminary results on the application of AuNPs as gate material for NO, sensing are reported. The sensor is able to detect NO, with appreciable selectivity and low response towards the other tested gases (C3H6, CO, H-2, NH3).

    Keywords
    Gold Nanoparticle, FET, XPS, Gas Sensor
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-16140 (URN)10.1166/sl.2008.433 (DOI)
    Available from: 2009-01-08 Created: 2009-01-07 Last updated: 2018-02-19
    2. Electrochemically Synthesised Pd- and Au-nanoparticles as sensing layers in NOx-sensitive field effect devices
    Open this publication in new window or tab >>Electrochemically Synthesised Pd- and Au-nanoparticles as sensing layers in NOx-sensitive field effect devices
    Show others...
    2008 (Swedish)In: Smart Sensors and Sensing Technology / [ed] Subhas Chandra Mukhopadhyay and Gourab Sen Gupta, Berlin, Heidelberg: Springer , 2008, p. 63-75Conference paper, Published paper (Other academic)
    Abstract [en]

    An environmental pollutant of great concern is NOx (nitrogen monoxide and nitrogen dioxide). Here we report the utilisation of electrochemically synthesised gold and palladium nanoparticles as catalytically active gate material on gas sensitive field effect sensor devices. The synthesised nanoparticles have been characterised by TEM and XPS, and the morphology of the thermally treated nanostructured sensing layers has been investigated using SEM and XPS. Measurements on the gas response of the palladium as well as the gold nanoparticle sensors towards a number of analytes found in automotive gas exhausts were performed and their response patterns were compared. The initial gas response measurements show interesting sensing properties for both the gold and the palladium nanoparticle sensors towards NOx detection.

    Place, publisher, year, edition, pages
    Berlin, Heidelberg: Springer, 2008
    Series
    Lecture notes in Electrical Engineering, ISSN 1876-1100 ; 20
    Keywords
    NOx- sensor · gold · palladium · nanoparticle · field effect sensor
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-44313 (URN)10.1007/978-3-540-79590-2_5 (DOI)76301 (Local ID)978-3-540-79589-6 (ISBN)978-3-540-79590-2 (ISBN)76301 (Archive number)76301 (OAI)
    Conference
    The 2nd International Conference on Sensing Technology, ICST 2007, November 26-28, Massey, New Zealand
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2016-06-13Bibliographically approved
    3. Carbide and nanocomposite thin films in the Ti-Pt-C system
    Open this publication in new window or tab >>Carbide and nanocomposite thin films in the Ti-Pt-C system
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    2010 (English)In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 518, no 18, p. 5104-5109Article in journal (Refereed) Published
    Abstract [en]

    Thin films in the Ti-Pt-C system were deposited by non-reactive, DC-magnetron sputtering. Samples were characterised using X-ray photoelectron spectroscopy, X-ray diffraction, and transmission electron microscopy. A previously not reported metastable solid solution carbide, (Ti1-xPtx)C-y with a Pt/Ti ratio of up to 0.43 was observed. This solid solution phase was present both as single phase in polycrystalline samples, and together with amorphous carbon (a-C) in nanocomposite samples. Annealing of nanocomposite samples leads to the decomposition of the solid solution phase and the formation of a nc-TiCx/a-C/nc-Pt nanocomposite. Test sensors for automotive gas exhausts manufactured from such a three-phase material suffer from complete oxidation of the coating at 400 degrees C with no observed sensor activity.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2010
    Keywords
    Solid solution carbide; Nanocomposite; Sputtering; Gas sensor; Annealing; Transmission electron microscopy; X-ray photoelectron spectroscopy; X-ray diffraction
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-58177 (URN)10.1016/j.tsf.2010.03.017 (DOI)000279659900013 ()
    Note
    Original Publication: Erik Lewin, Kristina Buchholt, Jun Lu, Lars Hultman, Anita Lloyd Spetz and Ulf Jansson, Carbide and nanocomposite thin films in the Ti-Pt-C system, 2010, Thin Solid Films, (518), 18, 5104-5109. http://dx.doi.org/10.1016/j.tsf.2010.03.017 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2010-08-11 Created: 2010-08-09 Last updated: 2017-12-12
    4. Ohmic contact properties of magnetron sputtered Ti3SiC2 on n- and p-type 4H-silicon carbide
    Open this publication in new window or tab >>Ohmic contact properties of magnetron sputtered Ti3SiC2 on n- and p-type 4H-silicon carbide
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    2011 (English)In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 98, no 4, p. 042108-Article in journal (Refereed) Published
    Abstract [en]

    Epitaxial Ti3SiC2 (0001) thin film contacts were grown on doped 4H-SiC (0001) using magnetron sputtering in an ultra high vacuum system. The specific contact resistance was investigated using linear transmission line measurements. Rapid thermal annealing at 950 degrees C for 1 min of as-deposited films yielded ohmic contacts to n-type SiC with contact resistances in the order of 10(-4) Omega cm(2). Transmission electron microscopy shows that the interface between Ti3SiC2 and n-type SiC is atomically sharp with evidence of interfacial ordering after annealing.

    Place, publisher, year, edition, pages
    American Institute of Physics, 2011
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-67170 (URN)10.1063/1.3549198 (DOI)000286676600025 ()
    Note

    Original Publication: Kristina Buchholt, R Ghandi, M Domeij, C-M Zetterling, Jun Lu, Per Eklund, Lars Hultman and Anita Lloyd Spetz, Ohmic contact properties of magnetron sputtered Ti3SiC2 on n- and p-type 4H-silicon carbide, 2011, APPLIED PHYSICS LETTERS, (98), 4, 042108. http://dx.doi.org/10.1063/1.3549198 Copyright: American Institute of Physics http://www.aip.org/

    Available from: 2011-04-01 Created: 2011-04-01 Last updated: 2017-12-11Bibliographically approved
    5. Growth and characterization of epitaxial Ti3GeC2 thin films on 4H-SiC(0001)
    Open this publication in new window or tab >>Growth and characterization of epitaxial Ti3GeC2 thin films on 4H-SiC(0001)
    Show others...
    2012 (English)In: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 343, no 1, p. 133-137Article in journal (Refereed) Published
    Abstract [en]

    Epitaxial Ti3GeC2 thin films were deposited on 4 degrees off-cut 4H-SiC(0001) using magnetron sputtering from high purity Ti, C, and Ge targets. Scanning electron microscopy and helium ion microscopy show that the Ti3GeC2 films grow by lateral step-flow with {11 (2) over bar0} faceting on the SiC surface. Using elastic recoil detection analysis, atomic force microscopy, and X-Ray diffraction the films were found to be substoichiometric in Ge with the presence of small Ge particles at the surface of the film.

    Place, publisher, year, edition, pages
    Elsevier, 2012
    Keywords
    Surface structure, Atomic force microscopy, Helium ion microscopy, Physical vapor deposition processes, Titanium compound
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-77103 (URN)10.1016/j.jcrysgro.2012.01.020 (DOI)000302422300023 ()
    Note

    Funding Agencies|VINN Excellence Center in Research and Innovation on Functional Nanoscale Materials (FunMat) by Swedish Governmental Agency for Innovation Systems (VINNOVA)||

    The status of this article was previously Manuscript.

    Available from: 2012-05-04 Created: 2012-05-04 Last updated: 2017-12-07
    6. Step-flow growth of nanolaminate Ti3SiC2 epitaxial layers on 4H-SiC(0 0 0 1)
    Open this publication in new window or tab >>Step-flow growth of nanolaminate Ti3SiC2 epitaxial layers on 4H-SiC(0 0 0 1)
    Show others...
    2011 (English)In: SCRIPTA MATERIALIA, ISSN 1359-6462, Vol. 64, no 12, p. 1141-1144Article in journal (Refereed) Published
    Abstract [en]

    Epitaxial Ti3SiC2(0 0 0 1) films were deposited on 4 degrees off-cut 4H-SiC(0 0 0 1) wafers using magnetron sputtering. A lateral step-flow growth mechanism of the Ti3SiC2 was discovered by X-ray diffraction, elastic recoil detection analysis, atomic force microscopy and electron microscopy. Helium ion microscopy revealed contrast variations on the Ti3SiC2 terraces, suggesting a mixed Si and Ti(C) termination. Si-rich growth conditions results in Ti3SiC2 layers with pronounced {1 1 (2) over bar 0) faceting and off-oriented TiSi2 crystallites, while stoichiometric growth yields truncated {1 (1) over bar 0 0) terrace edges.

    Place, publisher, year, edition, pages
    Elsevier Science B.V., Amsterdam., 2011
    Keywords
    Sputtering, Atomic force microscopy (AFM), Helium ion microscopy (HIM), Transmission electron microscopy (TEM), Crystal structure
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-68684 (URN)10.1016/j.scriptamat.2011.03.013 (DOI)000290422300019 ()
    Note
    Original Publication: Kristina Buchholt, Per Eklund, Jens Jensen, Jun Lu, Anita Lloyd Spetz and Lars Hultman, Step-flow growth of nanolaminate Ti3SiC2 epitaxial layers on 4H-SiC(0 0 0 1), 2011, SCRIPTA MATERIALIA, (64), 12, 1141-1144. http://dx.doi.org/10.1016/j.scriptamat.2011.03.013 Copyright: Elsevier Science B.V., Amsterdam. http://www.elsevier.com/ Available from: 2011-05-27 Created: 2011-05-27 Last updated: 2016-08-31
    7. Phase-stabilization and substrate effects on nucleation and growth of (Ti,V)(n+1)GeC(n) thin films
    Open this publication in new window or tab >>Phase-stabilization and substrate effects on nucleation and growth of (Ti,V)(n+1)GeC(n) thin films
    Show others...
    2011 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 110, no 5, article id 053516Article in journal (Refereed) Published
    Abstract [en]

    Phase-pure epitaxial thin films of (Ti,V)(2)GeC have been grown onto Al(2)O(3)(0001) substrates via magnetron sputtering. The c lattice parameter is determined to be 12.59 A, corresponding to a 50/50 Ti/V solid solution according to Vegards law, and the overall (Ti,V): Ge: C composition is 2:1:1 as determined by elastic recoil detection analysis. The minimum temperature for the growth of (Ti,V)(2)GeC is 700 degrees C, which is the same as for Ti(2)GeC but higher than that required for V(2)GeC (450 degrees C). Reduced Ge content yields films containing (Ti,V)(3)GeC(2) and (Ti,V)(4)GeC(3). These results show that the previously unknown phases V(3)GeC(2) and V(4)GeC(3) can be stabilized through alloying with Ti. For films grown on 4H-SiC(0001), (Ti,V)(3)GeC(2) was observed as the dominant phase, showing that the nucleation and growth of (Ti,V)(n+1)GeC(n) is affected by the choice of substrate; the proposed underlying physical mechanism is that differences in the local substrate temperature enhance surface diffusion and facilitate the growth of the higher-order phase (Ti,V)(3)GeC(2) compared to (Ti,V)(2)GeC.

    Place, publisher, year, edition, pages
    American Institute of Physics (AIP), 2011
    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-71221 (URN)10.1063/1.3631087 (DOI)000294968600055 ()
    Note

    The status of this article was previously Manuscript and the original title was (Ti, V)n+1GeCn thin films.

    Available from: 2011-10-07 Created: 2011-10-07 Last updated: 2017-12-08
  • 115.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Ghandi, R
    Royal Institute Technology, KTH.
    Domeij, M
    Royal Institute Technology, KTH.
    Zetterling, C M
    Royal Institute Technology, KTH.
    Behan, G
    Trinity College Dublin.
    Zhang, H
    Trinity College Dublin.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Growth and characterization of epitaxial Ti3GeC2 thin films on 4H-SiC(0001)2012In: Journal of Crystal Growth, ISSN 0022-0248, E-ISSN 1873-5002, Vol. 343, no 1, p. 133-137Article in journal (Refereed)
    Abstract [en]

    Epitaxial Ti3GeC2 thin films were deposited on 4 degrees off-cut 4H-SiC(0001) using magnetron sputtering from high purity Ti, C, and Ge targets. Scanning electron microscopy and helium ion microscopy show that the Ti3GeC2 films grow by lateral step-flow with {11 (2) over bar0} faceting on the SiC surface. Using elastic recoil detection analysis, atomic force microscopy, and X-Ray diffraction the films were found to be substoichiometric in Ge with the presence of small Ge particles at the surface of the film.

  • 116.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Jensen, Jens
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Step-flow growth of nanolaminate Ti3SiC2 epitaxial layers on 4H-SiC(0 0 0 1)2011In: SCRIPTA MATERIALIA, ISSN 1359-6462, Vol. 64, no 12, p. 1141-1144Article in journal (Refereed)
    Abstract [en]

    Epitaxial Ti3SiC2(0 0 0 1) films were deposited on 4 degrees off-cut 4H-SiC(0 0 0 1) wafers using magnetron sputtering. A lateral step-flow growth mechanism of the Ti3SiC2 was discovered by X-ray diffraction, elastic recoil detection analysis, atomic force microscopy and electron microscopy. Helium ion microscopy revealed contrast variations on the Ti3SiC2 terraces, suggesting a mixed Si and Ti(C) termination. Si-rich growth conditions results in Ti3SiC2 layers with pronounced {1 1 (2) over bar 0) faceting and off-oriented TiSi2 crystallites, while stoichiometric growth yields truncated {1 (1) over bar 0 0) terrace edges.

  • 117.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Ghandi, R
    Royal Institute of Technology.
    Domeij, M
    Royal Institute of Technology.
    Zetterling, C-M
    Royal Institute of Technology.
    Lu, Jun
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Eklund, Per
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Hultman, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Thin Film Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Ohmic contact properties of magnetron sputtered Ti3SiC2 on n- and p-type 4H-silicon carbide2011In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 98, no 4, p. 042108-Article in journal (Refereed)
    Abstract [en]

    Epitaxial Ti3SiC2 (0001) thin film contacts were grown on doped 4H-SiC (0001) using magnetron sputtering in an ultra high vacuum system. The specific contact resistance was investigated using linear transmission line measurements. Rapid thermal annealing at 950 degrees C for 1 min of as-deposited films yielded ohmic contacts to n-type SiC with contact resistances in the order of 10(-4) Omega cm(2). Transmission electron microscopy shows that the interface between Ti3SiC2 and n-type SiC is atomically sharp with evidence of interfacial ordering after annealing.

  • 118.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Ieva, E.
    Linköping University, Department of Physics, Chemistry and Biology, Chemistry.
    Käll, Per-Olov
    Linköping University, Department of Physics, Chemistry and Biology, Physical Chemistry. Linköping University, The Institute of Technology.
    Ojamäe, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Physical Chemistry. Linköping University, The Institute of Technology.
    Torsi, L
    Universita degli Studi di Bari, Italy.
    Lutic, D.
    Växjö universitet.
    Strand, M
    Växjö universitet.
    Sanati, M.
    Växjö universitet.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    FET devices with gold nanoparticle gate material as nitrogen oxide gas sensors2006In: Proceedings from E-MRS 2006, Nice France, May 29- June 1, 2006, 2006, p. 87-92Conference paper (Refereed)
    Abstract [en]

       

  • 119.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Ieva, Eliana
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Torsi, L
    Dipartimento di Chimica, Universita degli Studi di Bari, Italy.
    Cioffi, N
    Dipartimento di Chimica, Universita degli Studi di Bari, Italy.
    Colaianni, L
    Dipartimento di Chimica, Universita degli Studi di Bari, Italy.
    Söderlind, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Käll, Per-Olov
    Linköping University, Department of Physics, Chemistry and Biology, Physical Chemistry. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    A comparison between the use of Pd- and Au-nanoparticles as sensing layers in a field effect NOx-sensitive sensor2007In: The 2nd Conference on Sensing Technology ICST,2007, 2007, p. 87-92Conference paper (Refereed)
  • 120.
    Buchholt, Kristina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Leva, E
    Dipartimento di Chimica, Università degli Studi di Bari, Bari, Italy.
    Torsi, L
    Dipartimento di Chimica, Università degli Studi di Bari, Bari, Italy.
    Cioffi, N
    Dipartimento di Chimica, Università degli Studi di Bari, Bari, Italy.
    Colaianni, L
    Dipartimento di Chimica, Università degli Studi di Bari, Bari, Italy.
    Söderlind, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Käll, Per-Olov
    Linköping University, Department of Physics, Chemistry and Biology, Physical Chemistry. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Electrochemically Synthesised Pd- and Au-nanoparticles as sensing layers in NOx-sensitive field effect devices2008In: Smart Sensors and Sensing Technology / [ed] Subhas Chandra Mukhopadhyay and Gourab Sen Gupta, Berlin, Heidelberg: Springer , 2008, p. 63-75Conference paper (Other academic)
    Abstract [en]

    An environmental pollutant of great concern is NOx (nitrogen monoxide and nitrogen dioxide). Here we report the utilisation of electrochemically synthesised gold and palladium nanoparticles as catalytically active gate material on gas sensitive field effect sensor devices. The synthesised nanoparticles have been characterised by TEM and XPS, and the morphology of the thermally treated nanostructured sensing layers has been investigated using SEM and XPS. Measurements on the gas response of the palladium as well as the gold nanoparticle sensors towards a number of analytes found in automotive gas exhausts were performed and their response patterns were compared. The initial gas response measurements show interesting sensing properties for both the gold and the palladium nanoparticle sensors towards NOx detection.

  • 121.
    Bur, Christian
    et al.
    Saarland University, Saarbruecken, Germany.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Reimann, P
    Saarland University, Saarbruecken, Germany.
    Schütze, Andreas
    Saarland University, Saarbruecken, Germany.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Increasing the selectivity of Pt-gate SiC field effect gas sensors by dynamic temperature modulation2010In: IEEE Sensors 2010, 2010, p. 1267-Conference paper (Refereed)
  • 122.
    Bur, Christian
    et al.
    Saarland University, Saarbruecken, Germany.
    Reimann, P.
    Saarland University, Saarbruecken, Germany.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Schütze, Andreas
    Saarland University, Saarbruecken, Germany.
    Temperature cycled operation of SiC field effect gas sensors: increasing the selectivity for improved sensor systems2011In: AIP. Conf. Proc ISOEN 2011 vol 1362, 2011, p. 91-92Conference paper (Refereed)
    Abstract [en]

    In order to detect and quantify nitrogen oxides (NOx) in a mixture of typical exhaust gases a diode coupled FET has been investigated using Temperature Cycled Operation. This approach, originally developed for metal oxide gas sensors, is quite new for GasFETs but preliminary studies proved that it is suitable for GasFETs as well. In this paper the basic concept was improved by a temperature cycle tailored to NOx detection. Multivariate statistics have been used to evaluate the sensor data. Measurements have shown that with a piecewise extraction of features, a quantification of NO with additional NO2 is possible in the background of exhaust gases. Thus, the detection of NOx and especially the determination of the concentration can be improved.

  • 123.
    Bur, Christian
    et al.
    Saarland University, Saarbruecken, Germany.
    Reimann, P.
    Saarland University, Saarbruecken, Germany.
    Schütze, Andreas
    Saarland University, Saarbruecken, Germany.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    New method for selectivity enhancement of SiC field effect gas sensors for quantification of NOx2011In: Proc. SPIE 8066, 2011Conference paper (Refereed)
  • 124.
    Bur, Christian
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Reimann, Peter
    University of Saarland, Germany .
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Schuetze, Andreas
    University of Saarland, Germany .
    New method for selectivity enhancement of SiC field effect gas sensors for quantification of NO (x)2012In: Microsystem Technologies: Micro- and Nanosystems Information Storage and Processing Systems, ISSN 0946-7076, E-ISSN 1432-1858, Vol. 18, no 7-8, p. 1015-1025Article in journal (Refereed)
    Abstract [en]

    A silicon carbide based enhancement type metal insulator field effect transistor with porous gate metallization has been investigated as a total NO (x) sensor operated in a temperature cycling mode. This operating mode is quite new for gas sensors based on the field effect but promising results have been reported earlier. Based on static investigations we have developed a suitable T-cycle optimized for NO (x) detection and quantification in a mixture of typical exhaust gases (CO, C2H4, and NH3). Significant features describing the shape of the sensor response have been extracted and evaluated with multivariate statistics (e.g. linear discriminant analysis) allowing quantification of NO (x) . Additional cleaning-cycles every 30 min improve the stability of the sensor further. With this kind of advanced signal processing the influence of sensor drift and cross sensitivity to ambient gases can be reduced effectively. Measurements have proven that different concentrations of NO (x) can be detected even in a changing mixture of other typical exhaust gases under dry and humid conditions. In addition to that, unknown concentrations of NO (x) can be detected based on a small set of training data. It can be concluded that the performance of GasFETs for NO (x) determination can be enhanced considerably with temperature cycling and appropriate signal processing.

  • 125.
    Bur, Christian
    et al.
    University of Saarland.
    Reimann, Peter
    Dillinger Hutte GTS.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Schuetze, Andreas
    University of Saarland.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Increasing the Selectivity of Pt-Gate SiC Field Effect Gas Sensors by Dynamic Temperature Modulation2012In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 12, no 6Article in journal (Refereed)
    Abstract [en]

    Based on a diode coupled silicon carbide field effect transistor (FET) with platinum as catalytic gate material, the influence of dynamic temperature modulation on the selectivity of gas analysis sensors FETs has been investigated. This operating mode, studied intensively for semiconductor gas sensors, has only recently been applied to FETs. A suitable temperature cycle for detection of typical exhaust gases (CO, NO, C3H6, H-2, NH3) was developed and combined with appropriate signal processing. The sensor data were evaluated using multivariate statistics, e.g., linear discriminant analysis. Measurements have proven that typical exhaust gases can be discriminated in backgrounds with 0, 10, and 20% oxygen. Furthermore, we are able to quantify the mentioned gases and to determine unknown concentrations based on training data. Very low levels of relative humidity below a few percent influence the sensor response considerably but for higher levels the cross interference of humidity is negligible. In addition, experiments regarding stability and reproducibility were performed.

  • 126.
    Bur, Christian
    et al.
    Saarland University, Saarbruecken, Germany.
    Schütze, Andreas
    Saarland University, Saarbruecken, Germany.
    Andersson, Mike
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Hierarcical strategy for quantification of NOx in a varying background of typical exhaust gases2011In: Proc. IEEE Sensors 2011, Limerick, Ireland, October 28-31, IEEE , 2011, p. 137-140Conference paper (Refereed)
    Abstract [en]

    Silicon carbide based metal insulator field effect transistors (MISiC FET) with a catalytic gate metallization were used in temperature cycled operating mode (TCO) in order to improve the selectivity of the sensor. This approach obtaining multiple data from a single sensor, therefore known as a virtual multisensor, was originally developed for metal oxide sensors but earlier work proved the suitability for MISiC FETs as well. This strategy was now tailored to the quantification of NOx in a mixture of typical exhaust gases (CO, HC, plus NH3). Data was evaluated with multivariate statistics e.g. Linear Discriminant Analysis. In order to suppress the influence of varying background a hierarchical approach was used. Results show that quantification of NOx is possible even in a changing background.

  • 127.
    Carlsson, Andreas
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Krantz-Rulcker, C
    Linkoping Univ, Dept Phys & Measurement Technol, S SENCE, S-58183 Linkoping, Sweden.
    Winquist, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    An electronic tongue as a tool for wet-end monitoring2001In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 16, no 4, p. 319-326Article in journal (Refereed)
    Abstract [en]

    An electronic tongue based on voltammetry and multivariate signal analysis has been evaluated as a tool for characterisation of the chemistry of the wet-end of a paper machine. Measurements were performed on head-box furnish samples from a tissue machine. PLS models, based on electronic tongue data, were made of five reference parameters - pH, conductivity, cationic demand, zeta potential and turbidity. The correlation coefficients for predicted values were for all parameters higher than 0.88. Highly correlated reference parameters might be part of the explanation for the high correlation factors. Still the results, being based on data without e.g. drift compensation, indicate that the electronic tongue has very promising features as a tool for wet-end control. Flexibility, fast response and wide sensitivity spectra make the electronic tongue suitable for a variety of applications.

  • 128.
    Carlsson, Jenny
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Interaction Studies in Complex Fluids with Optical Biosensors2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis interactions in complex fluids, such as serum and meat juice, were analysed with optical biosensor techniques.

    Panels of lectins immobilised on gold surfaces were used for investigation of differences in protein glycosylation pattern in sera and meat juices between various species. The present panel was also used for investigation of global glycosylation changes of serum proteins in type 1 diabetes patients. Biorecognition was evaluated with null ellipsometry and scanning ellipsometry combined with multivariate data analysis techniques (MVDA). Principal component analysis (PCA) showed that the lectin panel enabled discrimination between sera from the different species as well as for the different meat juices. The results also indicate that there is a measurable global alteration in glycosylation pattern of serum proteins in type 1 diabetic patients compared to healthy subjects. Using an artificial neuronal net (ANN), it was also possible to correctly categorise unknown serum samples into their respective class or group. The analytical potential of combining information from lectin panels with multivariate data analysis was thereby demonstrated.

    Also, a sensitive and specific method based on surface plasmon resonance (SPR) for detection of insulin autoantibodies (IAA) in serum samples from individuals at high risk of developing type 1 diabetes (T1D) has been developed. When measuring trace molecules, such as autoantibodies, in undiluted sera with label-free techniques like SPR, non-specific adsorption of matrix proteins to the sensor surface is often a problem, since it causes a signal that masks the analyte response. The developed method is an indirect competitive immunoassay designed to overcome these problems. Today, IAA is mainly measured in radio immunoassays (RIAs), which are time consuming and require radioactively labelled antigen. With our SPR-based immunoassay the overall assay time is reduced by a factor of >100 (from 4 days to 50 min), while sensitivity is maintained at a level comparable to that offered by RIA. Finally, the assay was used in a screening study of newly diagnosed type 1 diabetes patients and non-diabetic subjects.

    List of papers
    1. Investigation of sera from various species by using lectin affinity arrays and scanning ellipsometry
    Open this publication in new window or tab >>Investigation of sera from various species by using lectin affinity arrays and scanning ellipsometry
    Show others...
    2005 (English)In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 530, no 2, p. 167-171Article in journal (Refereed) Published
    Abstract [en]

    Serum proteins of different species and of different human blood groups exhibit various protein glycosylation patterns. Sera from human, pig, sheep and guinea pig have been applied to a panel of eight different lectins immobilized on a gold wafer. The biorecognition has been evaluated with scanning ellipsometry and the two-dimensional matrices obtained have been treated with image analysis and MVDA for evaluation. The results showed a clear difference in protein binding pattern between the different species and thereby separation of the different sera could be made. Dendograms indicate that human and pig sera are the most related of the four different sera investigated.

    Keywords
    Serum proteins, lectins, scanning ellipsometry, image analysis, multivariate data analysis
    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:liu:diva-12466 (URN)10.1016/j.aca.2004.09.022 (DOI)
    Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2017-12-13Bibliographically approved
    2. Biosensor discrimination of meat juice from various animals using a lectin panel and ellipsometry
    Open this publication in new window or tab >>Biosensor discrimination of meat juice from various animals using a lectin panel and ellipsometry
    2005 (English)In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 547, no 2, p. 229-236Article in journal (Refereed) Published
    Abstract [en]

    In this work, simple microcontact printed gold-wafers were used to make a lectin panel for investigation and discrimination of different meat juices from fresh meat of cattle, chicken, pig, cod, turkey and lamb. Seven different lectins were thus attached to gold surfaces using the streptavidin–biotin method. Lectins recognize and bind specifically to carbohydrate structures present on different proteins. The biorecognition was evaluated with null ellipsometry and the data obtained was related to an internal standard of lactoferrin. The data was evaluated with multivariate data analysis techniques to identify possible discrimination or grouping of data. Scanning ellipsometry was used for visualization of the binding pattern of the lectins and the meat juice proteins. The two-dimensional images obtained could be used to visualize the protein distribution, furthermore, to exclude anomalies. The results showed that the different meat juices from the six different species: cattle, chicken, pig, cod, turkey and lamb could be discriminated from each other. The results showed to be more repetitive for the mammalian meat juices. Using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated.

    Keywords
    Lectin panel; Ellipsometry; Meat juice; Multivariate data analysis
    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:liu:diva-12467 (URN)10.1016/j.aca.2005.05.054 (DOI)
    Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2017-12-13Bibliographically approved
    3. Detection of global glycosylation changes of serum proteins in type 1 diabetes using a lectin panel and multivariate data analysis
    Open this publication in new window or tab >>Detection of global glycosylation changes of serum proteins in type 1 diabetes using a lectin panel and multivariate data analysis
    Show others...
    2008 (English)In: Talanta: The International Journal of Pure and Applied Analytical Chemistry, ISSN 0039-9140, E-ISSN 1873-3573, Vol. 76, no 2, p. 333-337Article in journal (Refereed) Published
    Abstract [en]

    Global glycosylation changes of serum proteins in type 1 diabetic patients have in this paper been investigated based on the interaction of the saccharide moiety of serum proteins with different lectins. Lectins are proteins, which bind carbohydrates specifically and reversibly. Panels with lectins of various carbohydrate specificities were immobilized on gold surfaces. Sera from healthy individuals, newly diagnosed type 1 diabetes patients and type 1 diabetes patients having had the disease for 4–6 years, respectively, were applied to the lectin panel. The biorecognition was evaluated with null ellipsometry. Data obtained were related to an internal standard of lactoferrin. Multivariate data analysis (MVDA) techniques were used to analyze data.

    Principal component analysis showed that the lectin panel enabled discrimination between sera from the three different above-mentioned groups. Using an artificial neuronal net (ANN), it was possible to correctly categorize unknown serum samples into one of the three groups.

     

    Keywords
    Lectin panel, Glycosylation changes, Type 1 diabetes, Ellipsometry, MVDA
    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:liu:diva-12468 (URN)10.1016/j.talanta.2008.02.046 (DOI)
    Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2017-12-13Bibliographically approved
    4. An indirect competitive immunoassay for insulin autoantibodies based on surface plasmon resonance
    Open this publication in new window or tab >>An indirect competitive immunoassay for insulin autoantibodies based on surface plasmon resonance
    Show others...
    2008 (English)In: Biosensors and Bioelectronics, ISSN 0956-5663, Vol. 24, no 4, p. 876-881Article in journal (Refereed) Published
    Abstract [en]

    We have developed a sensitive and specific method based on surface plasmon resonance (SPR) for detection of insulin autoantibodies (IAA) in serum samples from individuals at high risk of developing type 1 diabetes (T1D). When measuring trace molecules in undiluted sera with label-free techniques like SPR, non-specific adsorption of matrix proteins to the sensor surface is often a problem, since it causes a signal that masks the analyte response. The developed method is an indirect competitive immunoassay designed to overcome these problems. Today, IAA is mainly measured in radio immunoassays (RIAs), which are time consuming and require radioactively labeled antigen. With our SPR-based immunoassay the overall assay time is reduced by a factor of >100 (4 days to 50 min), while sensitivity is maintained at a level comparable to that offered by RIA.

    Keywords
    SPR, Type 1 diabetes, Insulin autoantibodies, Indirect competitive immunoassay, RIA
    National Category
    Other Basic Medicine
    Identifiers
    urn:nbn:se:liu:diva-12469 (URN)10.1016/j.bios.2008.07.018 (DOI)
    Note
    The status of article IV on the day of defence was: Accepted.Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2018-01-13Bibliographically approved
    5. Determination of insulin autoantibodies using surface plasmon resonance: A screening study of newly diagnosed type 1 diabetes patients
    Open this publication in new window or tab >>Determination of insulin autoantibodies using surface plasmon resonance: A screening study of newly diagnosed type 1 diabetes patients
    Show others...
    2008 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    We have investigated the screening potential of a surface plasmon resonance (SPR)-based indirectcompetitive immunoassay for quantification of insulin autoantibodies (IAA) in sera from childrennewly diagnosed with type 1 diabetes (T1D), using a radioimmunoassay (RIA) as reference technique.The two methods agreed well with respect to sample classification of 54 sera from newly diagnosedT1D children and 32 reference sera from non-diabetic children. Interestingly, five samples from newlydiagnosed T1D patients classified as IAA-negative according to RIA were IAA-positive with the SPRbasedassay, suggesting that the SPR-based assay might provide a higher sensitivity than the referenceRIA. However, 14 percent of the analyzed samples (five samples from non-diabetics and seven fromnewly diagnosed T1D patients) gave rise to anomalously high and easily distinguishable responses withthe SPR-based method, precluding IAA-quantification. A considerable part of the paper is devoted to adiscussion of possible causes of these anomalous responses. They were not due to temporary changesin the status of the patients, such as infections at the time of sampling, and also not related tocomplement activation. It is speculated whether a plausible explanation should instead be sought in theexistence of anti-idiotypic antibodies to IAA.

    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:liu:diva-12470 (URN)
    Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2015-10-05Bibliographically approved
  • 129.
    Carlsson, Jenny
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Surface analytical methods and multivariate data analysis applied to lectin panels2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis lectin panels on gold wafers were utilized to investigate sera from different mammals and meat juices from various species of animals. Lectins, which are a group of diverse, natural proteins recognize and bind to different carbohydrate structures present on the sera proteins and on the proteins in the different meat juices. The binding patterns from the relatively unspecific interactions between lectins and carbohydrate structures were evaluated with techniques based on ellipsometry. The resulting data was treated with multivariate data analysis (MVDA) techniques, especially principal component analysis (PCA), to identify separation or grouping of data.

    It was shown that lectin panels combined with ellipsometric techniques and MVDA could be used to separate sera from different mammals and also a possible relation between species could be seen. Meat juices from the different species evaluated were also possible to separate and using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated. In spite of its great analytical potential, not much work has yet been done utilizing MVDA together with bioanalytical methods. The results in this thesis however, show great potential for combining lectin panels with MVDA.

    This work, regarding lectin panels, was incorporated as a part of a EU-project, Nanocell. The aim of the Nanocell-project was to develop a biosensor consisting of a single biomolecule electrically interfaced to nanoelectrodes, which is sensed electronically/optically.

    List of papers
    1. Investigation of sera from various species by using lectin affinity arrays and scanning ellipsometry
    Open this publication in new window or tab >>Investigation of sera from various species by using lectin affinity arrays and scanning ellipsometry
    Show others...
    2005 (English)In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 530, no 2, p. 167-171Article in journal (Refereed) Published
    Abstract [en]

    Serum proteins of different species and of different human blood groups exhibit various protein glycosylation patterns. Sera from human, pig, sheep and guinea pig have been applied to a panel of eight different lectins immobilized on a gold wafer. The biorecognition has been evaluated with scanning ellipsometry and the two-dimensional matrices obtained have been treated with image analysis and MVDA for evaluation. The results showed a clear difference in protein binding pattern between the different species and thereby separation of the different sera could be made. Dendograms indicate that human and pig sera are the most related of the four different sera investigated.

    Keywords
    Serum proteins, lectins, scanning ellipsometry, image analysis, multivariate data analysis
    National Category
    Chemical Sciences
    Identifiers
    urn:nbn:se:liu:diva-12466 (URN)10.1016/j.aca.2004.09.022 (DOI)
    Available from: 2008-09-06 Created: 2008-09-06 Last updated: 2017-12-13Bibliographically approved
    2. Separation of meat juice from various animals using a lectin panel and ellipsometry
    Open this publication in new window or tab >>Separation of meat juice from various animals using a lectin panel and ellipsometry
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    In this work simple microcontact printed gold-wafers were used to make a lectin panel for investigation and separation of different meat juices from fresh meat of cattle, chicken, pig, cod, turkey and lamb. Seven different lectins were thus attached to gold surfaces using the streptavidin-biotin method. Lectins recognize and bind specifically to carbohydrate structures present on different proteins. The bio-recognition was evaluated with null ellipsometry and the data obtained was related to an internal standard of lactoferrin. The data was evaluated with multivariate data analysis techniques to identify possible separation or grouping of data. Scanning ellipsometry was used for visualization of the binding pattern of the lectins and the meat juice proteins. The 2-dimensional images obtained could be used to visualize the protein distribution, furthermore, to exclude anomalies. The results showed that the different meat juices could be separated from each other. Using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated.

    National Category
    Engineering and Technology
    Identifiers
    urn:nbn:se:liu:diva-100839 (URN)
    Available from: 2013-11-13 Created: 2013-11-13 Last updated: 2013-11-13
  • 130.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Gullstrand, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences.
    Ludvigsson, Johnny
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Detection of global glycosylation changes of serum proteins in type 1 diabetes using a lectin panel and multivariate data analysis2008In: Talanta: The International Journal of Pure and Applied Analytical Chemistry, ISSN 0039-9140, E-ISSN 1873-3573, Vol. 76, no 2, p. 333-337Article in journal (Refereed)
    Abstract [en]

    Global glycosylation changes of serum proteins in type 1 diabetic patients have in this paper been investigated based on the interaction of the saccharide moiety of serum proteins with different lectins. Lectins are proteins, which bind carbohydrates specifically and reversibly. Panels with lectins of various carbohydrate specificities were immobilized on gold surfaces. Sera from healthy individuals, newly diagnosed type 1 diabetes patients and type 1 diabetes patients having had the disease for 4–6 years, respectively, were applied to the lectin panel. The biorecognition was evaluated with null ellipsometry. Data obtained were related to an internal standard of lactoferrin. Multivariate data analysis (MVDA) techniques were used to analyze data.

    Principal component analysis showed that the lectin panel enabled discrimination between sera from the three different above-mentioned groups. Using an artificial neuronal net (ANN), it was possible to correctly categorize unknown serum samples into one of the three groups.

     

  • 131.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Gullstrand, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences.
    Westermark, Gunilla
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Ludvigsson, Johnny
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Paediatrics and Gynecology and Obstetrics, Department of Paediatrics in Linköping.
    Enander, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Liedberg, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    An indirect competitive immunoassay for insulin autoantibodies based on surface plasmon resonance2008In: Biosensors and Bioelectronics, ISSN 0956-5663, Vol. 24, no 4, p. 876-881Article in journal (Refereed)
    Abstract [en]

    We have developed a sensitive and specific method based on surface plasmon resonance (SPR) for detection of insulin autoantibodies (IAA) in serum samples from individuals at high risk of developing type 1 diabetes (T1D). When measuring trace molecules in undiluted sera with label-free techniques like SPR, non-specific adsorption of matrix proteins to the sensor surface is often a problem, since it causes a signal that masks the analyte response. The developed method is an indirect competitive immunoassay designed to overcome these problems. Today, IAA is mainly measured in radio immunoassays (RIAs), which are time consuming and require radioactively labeled antigen. With our SPR-based immunoassay the overall assay time is reduced by a factor of >100 (4 days to 50 min), while sensitivity is maintained at a level comparable to that offered by RIA.

  • 132.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Gullstrand, Camilla
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences.
    Westermark, Gunilla
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Ludvigsson, Johnny
    Linköping University, Department of Clinical and Experimental Medicine, Pediatrics. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Enander, Karin
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics. Linköping University, The Institute of Technology.
    Liedberg, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics. Linköping University, The Institute of Technology.
    Determination of insulin autoantibodies using surface plasmon resonance: A screening study of newly diagnosed type 1 diabetes patients2008Manuscript (preprint) (Other academic)
    Abstract [en]

    We have investigated the screening potential of a surface plasmon resonance (SPR)-based indirectcompetitive immunoassay for quantification of insulin autoantibodies (IAA) in sera from childrennewly diagnosed with type 1 diabetes (T1D), using a radioimmunoassay (RIA) as reference technique.The two methods agreed well with respect to sample classification of 54 sera from newly diagnosedT1D children and 32 reference sera from non-diabetic children. Interestingly, five samples from newlydiagnosed T1D patients classified as IAA-negative according to RIA were IAA-positive with the SPRbasedassay, suggesting that the SPR-based assay might provide a higher sensitivity than the referenceRIA. However, 14 percent of the analyzed samples (five samples from non-diabetics and seven fromnewly diagnosed T1D patients) gave rise to anomalously high and easily distinguishable responses withthe SPR-based method, precluding IAA-quantification. A considerable part of the paper is devoted to adiscussion of possible causes of these anomalous responses. They were not due to temporary changesin the status of the patients, such as infections at the time of sampling, and also not related tocomplement activation. It is speculated whether a plausible explanation should instead be sought in theexistence of anti-idiotypic antibodies to IAA.

  • 133.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Mecklenburg, Michael
    nanoArc Corp, Newport Beach, CA, USA.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Danielsson, Bengt
    Pure and Applied Biochemistry, Lund University, PO Box 124, SE-22100 Lund, Sweden .
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Investigation of sera from various species by using lectin affinity arrays and scanning ellipsometry2005In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 530, no 2, p. 167-171Article in journal (Refereed)
    Abstract [en]

    Serum proteins of different species and of different human blood groups exhibit various protein glycosylation patterns. Sera from human, pig, sheep and guinea pig have been applied to a panel of eight different lectins immobilized on a gold wafer. The biorecognition has been evaluated with scanning ellipsometry and the two-dimensional matrices obtained have been treated with image analysis and MVDA for evaluation. The results showed a clear difference in protein binding pattern between the different species and thereby separation of the different sera could be made. Dendograms indicate that human and pig sera are the most related of the four different sera investigated.

  • 134.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Danielsson, Bengt
    Lund University, Lund, Sweden.
    Separation of meat juice from various animals using a lectin panel and ellipsometryManuscript (preprint) (Other academic)
    Abstract [en]

    In this work simple microcontact printed gold-wafers were used to make a lectin panel for investigation and separation of different meat juices from fresh meat of cattle, chicken, pig, cod, turkey and lamb. Seven different lectins were thus attached to gold surfaces using the streptavidin-biotin method. Lectins recognize and bind specifically to carbohydrate structures present on different proteins. The bio-recognition was evaluated with null ellipsometry and the data obtained was related to an internal standard of lactoferrin. The data was evaluated with multivariate data analysis techniques to identify possible separation or grouping of data. Scanning ellipsometry was used for visualization of the binding pattern of the lectins and the meat juice proteins. The 2-dimensional images obtained could be used to visualize the protein distribution, furthermore, to exclude anomalies. The results showed that the different meat juices could be separated from each other. Using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated.

  • 135.
    Carlsson, Jenny
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Danielsson, Bengt
    Pure and Applied Biochemistry, Lund University, SE-22 100 Lund, Sweden .
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Biosensor discrimination of meat juice from various animals using a lectin panel and ellipsometry2005In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 547, no 2, p. 229-236Article in journal (Refereed)
    Abstract [en]

    In this work, simple microcontact printed gold-wafers were used to make a lectin panel for investigation and discrimination of different meat juices from fresh meat of cattle, chicken, pig, cod, turkey and lamb. Seven different lectins were thus attached to gold surfaces using the streptavidin–biotin method. Lectins recognize and bind specifically to carbohydrate structures present on different proteins. The biorecognition was evaluated with null ellipsometry and the data obtained was related to an internal standard of lactoferrin. The data was evaluated with multivariate data analysis techniques to identify possible discrimination or grouping of data. Scanning ellipsometry was used for visualization of the binding pattern of the lectins and the meat juice proteins. The two-dimensional images obtained could be used to visualize the protein distribution, furthermore, to exclude anomalies. The results showed that the different meat juices from the six different species: cattle, chicken, pig, cod, turkey and lamb could be discriminated from each other. The results showed to be more repetitive for the mammalian meat juices. Using a simple model based on an artificial neuronal net, it was also possible to classify meat juices from the mammals investigated.

  • 136. Cerda, J
    et al.
    Morante, JR
    Lloyd-Spets, Anita
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    New tunnel Schottky SiC devices using mixed conduction ceramics2002In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 433-4, p. 949-952Article in journal (Refereed)
    Abstract [en]

    A new tunnel Schottky diode based on SiC and a mixed conductor of BaSnO3 as the gate has been investigated. I-V curves at different operating temperatures and two different gas atmospheres have been measured. The device shows sensitivity to oxygen, with maximum at 400degreesC. A model that describes the behaviour of the device is proposed, which takes into account the different types of conduction of the BaSnO3 due to the temperature.

  • 137.
    Cioffi, Nicola
    et al.
    University Bari Aldo Moro, Italy.
    Colaianni, Lorenzo
    Schaefer S E Europe SRL Italy.
    Ieva, Eliana
    Solvay Solexis SpA.
    Pilolli, Rosa
    University Bari Aldo Moro, Italy.
    Ditaranto, Nicoletta
    University Bari Aldo Moro, Italy.
    Daniela Angione, Maria
    University Bari Aldo Moro, Italy.
    Cotrone, Serafina
    University Bari Aldo Moro, Italy.
    Buchholt, Kristina
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Sabbatini, Luigia
    University Bari Aldo Moro, Italy.
    Torsi, Luisa
    University Bari Aldo Moro, Italy.
    Electrosynthesis and characterization of gold nanoparticles for electronic capacitance sensing of pollutants2011In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 56, no 10, p. 3713-3720Article in journal (Refereed)
    Abstract [en]

    In the present study, gold/surfactant core/shell colloidal nanoparticles with a controlled morphology and chemical composition have been obtained via the so-called sacrificial anode technique, carried out in galvanostatic mode. As synthesized Au-NPs had an average core diameter comprised between 4 and 8 nm, as a function of the electrochemical process experimental conditions. The UV-Vis characterization of gold nanocolloids showed clear spectroscopic size effects, affecting both the position and width of the nanoparticle surface plasmon resonance peak. The nanomaterial surface spectroscopic characterization showed the presence of two chemical states, namely nanostructured Au(0) (its abundance being higher than 90%) and Au(I). Au-NPs were then deposited on the top of a capacitive field effect sensor and subjected to a mild thermal annealing aiming at removing the excess of stabilizing surfactant molecules. Au-NP sensors were tested towards some gases found in automotive gas exhausts. The sensing device showed the largest response towards NOx, and much smaller - if any - responses towards interferent species such as NH3, H-2, CO, and hydrocarbons.

  • 138.
    Comina, German
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Chemical and Optical Sensor Systems. Linköping University, Faculty of Science & Engineering.
    Suska, Anke
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Filippini, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    PDMS lab-on-a-chip fabrication using 3D printed templates2014In: Lab on a Chip, ISSN 1473-0197, E-ISSN 1473-0189, Vol. 14, no 2, p. 424-430Article in journal (Refereed)
    Abstract [en]

    The fabrication of conventional PDMS on glass lab-on-a-chip (LOC) devices, using templates printed with a commercial (2299 US$) micro-stereo lithography 3D printer, is demonstrated. Printed templates replace clean room and photolithographic fabrication resources and deliver resolutions of 50 mu m, and up to 10 mu m in localized hindrances, whereas the templates are smooth enough to allow direct transfer and proper sealing to glass substrates. 3D printed templates accommodate multiple thicknesses, from 50 mu m up to several mm within the same template, with no additional processing cost or effort. This capability is exploited to integrate silicone tubing easily, to improve micromixer performance and to produce multilevel fluidics with simple access to independent functional surfaces, which is illustrated by time-resolved glucose detection. The templates are reusable, can be fabricated in under 20 min, with an average cost of 0.48 US$, which promotes broader access to established LOC configurations with minimal fabrication requirements, relieves LOC fabrication from design skills and provides a versatile LOC development platform.

  • 139.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Dehydrogenation of acetylene and ethylene studied on clean and oxygen covered palladium surfaces1986In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 173, p. 148-Article in journal (Refereed)
    Abstract [en]

    The interaction of acetylene and ethylene with a clean and oxygen covered Pd surface has been studied at a temperature of 473 K. The measurements were performed on a hydrogen sensitive Pd-MOS structure making it possible to obtain direct information on the dissociation of both hydrogen and oxygen containing species on a palladium surface. Desorption studies were also performed as well as ultraviolet photoelectron spectroscopy and work function measurements. The studies show that both acetylene and ethylene adsorb dissociatively at this temperature leaving mainly carbon on the surface. When an oxygen covered Pd surface is exposed to C2H2 or C2H4 carbon dioxide and water will be formed and desorb until the surface is oxygen free. In the case of acetylene the presence of preadsorbed oxygen does not block or prevent the C2H2 dissociation on the surface. For C2H4, a large preadsorbed oxygen coverage ( 0.45) will have an impeding effect on the dissociation. The CO2 desorption is oxygen coverage dependent contrary to the H2O desorption. This is due to the fact that hydrogen has a large lateral mobility on the surface while carbon has not. Both the CO2 and H2O reactions are, however, due to the same type of mechanisms.

  • 140.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Dehydrogenation rate of some unsaturated hydrocarbons on clean and oxygen covered palladium1987Conference paper (Refereed)
  • 141.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Detection of hydrogen from the photodissociative splitting of water through hydrogen-oxygen separation over a thin Pd film1991In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 70, p. 453-Article in journal (Refereed)
    Abstract [en]

    The photodissociative splitting of water has been studied in gas phase on a plane solid surface. A hydrogen sensitive Pd‐metal‐oxide‐semiconductor (MOS) structure was coated with 1–2 nm TiOx and exposed to water vapor and ultraviolet light. A natural separation of the produced hydrogen and oxygen occurs over the Pd film of the structure and the produced hydrogen is monitored by the electric behavior of the MOS device. The results suggest that suitably treated thin Pd membranes may be of interest for studying the continuous photodissociation of water.

  • 142.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Hydrocarbon dissociation on palladium studied with a hydrogen sensitive MOS structure1988In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 63, p. 207-Article in journal (Refereed)
    Abstract [en]

    The polycrystalline Pd surface of a hydrogen sensitive palladium‐silicon dioxide‐silicon [Pd‐MOS (metal‐oxide‐semiconductor)] structure has been exposed to small unsaturated hydrocarbons in the temperature range 300–500 K. Apart from the hydrogen response of the Pd‐MOS structure also work function (ΔΦ) and electron energy‐loss studies were performed. At 500 K the hydrocarbons dissociate completely upon adsorption and produce a surface with atomically adsorbed carbon. The Pd‐MOS structure can be used to observe both the dehydrogenation of the hydrocarbon molecules and the process of carbon adsorbing on the palladium surface. The sticking coefficient at this temperature for all hydrocarbons is close to unity. Furthermore, the hydrogen sensitivity of the structure is not drastically reduced by the adsorbed carbon. If the hydrocarbon adsorption is performed at 300 K there is still, at least on the initially clean surface, a large dehydrogenation. The dissociation is, however, not at all complete and there are considerable amounts of hydrocarbon species adsorbed for each gas. The induced work function shifts due to the different hydrocarbons vary from -1.0 to -1.7 eV. The hydrogen sensitivity of the Pd‐MOS structure is reduced for growing hydrocarbon coverages and disappears completely for work function shifts of -1.7 eV.

  • 143.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Reactions between hydrocarbon and an oxygen covered palladium surface1988In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 193, p. 109-Article in journal (Refereed)
    Abstract [en]

    Isothermic desorption studies where an oxygen covered polycrystalline Pd surface (T = 325–575 K) is exposed to small unsaturated hydrocarbons have been performed. The studied gases were acetylene, propene, propadiene, propyne, butene, butadiene, butyne, and also for comparison hydrogen. Electron energy loss spectroscopy (EELS) was available for adsorbate studies and a hydrogen sensitive Pd-MOS structure was used as a sample. The temperature limit for total dissociation is observed to decrease slightly for an oxygen covered surface compared to the clean surface. On an oxygen covered surface the dissociation is complete above 400 K and the reaction products are H2O, CO2, and adsorbed C. Varying the adsorption temperature, the carbon dioxide production is not detectable at room temperature, where all carbon is adsorbed and only water is formed, but increases to reach a constant level above 475 K. For temperatures above 400 K the licking coefficient is close to unity and there is no blocking due to preadsorbed oxygen (as there is for H2). Both the water and carbon dioxide formations are of Langmuir-Hinshelwood type but while the H2O desorption rate is found to depend only on impinging hydrocarbon flux the CO2 desorption rate depends also on the oxygen coverage.

  • 144.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Petersson, L.-G.
    The relative ionization gauge sensitivity of some unsaturated hydrocarbons1987In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 29, p. 331-Article in journal (Refereed)
    Abstract [en]

    By studying the water desorption rate from an oxygen covered Pd surface which is exposed to some unsaturated hydrocarbons (and hydrogen) the relative ionization gauge sensitivity of the hydrocarbons: acetylene, ethylene, propene, 1- and 2-butene, propadiene, 1,3-butadiene, propyne and butyne has been determined.

  • 145.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Petersson, L.-G.
    NO dissociation on polycrystalline Pd studied with a Pd-metal-oxide-semiconductor (Pd-MOS) structure1989In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 66, p. 1397-Article in journal (Refereed)
    Abstract [en]

    The dissociation probability of NO when adsorbed on polycrystalline Pd as a function of temperature (323–523 K) has been studied with a Pd‐metal‐oxide‐semiconductor (Pd‐MOS) structure. For comparison the same experiments were also carried out with O2, which adsorbs dissociatively in the whole temperature region, and with CO, which adsorbs molecularly. It was found that the Pd‐MOS structure can be used as a very sensitive sensor for NO dissociation and that dissociation of NO starts to be significant at temperatures around 400 K. The results are also compared with electron‐energy‐loss spectroscopy, ultraviolet photoemission spectroscopy, work‐function, and desorption studies.

  • 146.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Photodissociative splitting of water on surface modified metal-oxide-semiconductor (MOS) structures1990Conference paper (Refereed)
  • 147.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Unsaturated hydrocarbons on palladium1987Conference paper (Refereed)
  • 148.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Söderberg, D.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    A hydrogen-sensitive Pd-MOS structure working over a wide pressure range1984In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 17, p. 259-Article in journal (Refereed)
    Abstract [en]

    A Pd-MOS structure has been developed which has proven to be sensitive to hydrogen both in air at atmospheric pressures and in UHV. The ability to work over a wide pressure range makes it an interesting component in, e.g., the study of catalytic reactions involving hydrogen on metal surfaces. Here we demonstrate the hydrogen sensitivity of such a structure over a pressure range of 5x10-11 to 2 Torr.

  • 149.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Söderberg, Dennis
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    Linköping University. Linköping University, The Institute of Technology.
    The H2-O2 reaction on palladium studied over a large pressure range1984Conference paper (Refereed)
  • 150.
    Dannetun, Helen
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Söderberg, Dennis
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Petersson, L.-G.
    The H2-O2 reaction on palladium studied over a large pressure range: Independence of the microscopic sticking coefficients on surface condition1985In: Surface Science, ISSN 0039-6028, E-ISSN 1879-2758, Vol. 152/153, p. 559-Article in journal (Refereed)
    Abstract [en]

    We have studied the H2---O2 reaction on Pd over a large pressure range by letting the reaction take place on the Pd gate of a Pd-MOS structure. By measuring shifts in the capacitance versus voltage (C(V)) curve of the structure, the variation of the “free” hydrogen atom concentration can be monitored during the reaction. By combining these results with surface potential measurements and with photoelectron spectroscopy, we find a critical ratio of 0.4 where the surface turns from being oxygen dominated to being hydrogen dominated. The critical ratio is independent of the absolute pressures and of surface condition and shows no significant temperature dependence in the temperature range 50–200°C. This implies that hydrogen and oxygen have similar sticking coefficients at both clean and technical Pd surfaces. The conclusion is drawn that hydrogen (and oxygen) dissociation on Pd is a property of the Pd atom or cluster of Pd atoms and is not critically dependent on any long-range order parameter such as the surface electronic density of states.

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