liu.seSearch for publications in DiVA
Change search
Refine search result
1234567 151 - 200 of 328
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 151.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    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.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Comparative studies with surface plasmon resonance and free oscillation rheometry on the inhibition of platelets with cytochalasin E and monoclonal antibodies towards GPIIb/IIIa2002In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 17, no 9, p. 761-771Article in journal (Refereed)
    Abstract [en]

    In the haemostatic system a multitude of processes are intertwined in fine-tuned interactions that arrest bleeding, keep the circulatory system open, and the blood flowing. The occurrence of both surface and bulk interactions adds an additional dimension of complexity. These insights have led to the belief that global overall procedures can inform on the likely behaviour of the system in health and disease. Two sensing procedures: surface plasmon resonance (SPR), which senses surface interactions, and free oscillation rheometry (FOR), which senses interactions within the bulk, have been combined and evaluated. The contribution of blood cells, mainly platelets, to the SPR and FOR signals was explored by simultaneous SPR and FOR measurement during native whole blood coagulation, accelerated via the platelets through addition of SFLLRN peptide and inhibition of platelet aggregation with abciximab (ReoPro®) and of shape change with cytochalasin E. The SPR technique was found to be sensitive to inhibition of blood cell functions such as adhesion to and spreading on surfaces, as well as platelet aggregation. SPR seemed not to be directly sensitive to fibrin polymerisation in coagulating whole blood. The FOR technique detected the coagulation as a bulk phenomenon, i.e. the gelation of the blood due to fibrin formation was detected. The combination of SPR and FOR may therefore be suitable for studies on blood cell functions during coagulation.

  • 152.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    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.
    Rånby, Mats
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Surface plasmon resonance and free oscillation rheometry in combination: a useful approach for studies on haemostasis and interactions between whole blood and artificial surfaces2002In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 17, no 9, p. 747-759Article in journal (Refereed)
    Abstract [en]

    In haemostatic and biomaterial research biological processes at surfaces and in the bulk phase of the surface-contacting medium are important. The present work demonstrates the usefulness of the combination of surface plasmon resonance (SPR), sensitive to changes in refractive index at surfaces, and free oscillation rheometry (FOR), sensitive to rheological properties of the bulk, for simultaneous real-time measurements on coagulation and fibrinolysis of blood plasma and coagulation of whole blood. SFLLRN stimulated coagulation of native whole blood presented a higher SPR signal with different appearance than plasma coagulation, while the FOR signals corresponding to plasma and whole blood coagulation were similar. This indicated that the SPR technique was more sensitive to cell-surface interactions than to fibrin formation in whole blood during coagulation, while the FOR technique were equally sensitive to coagulation in whole blood and plasma. Spontaneous coagulation of native whole blood in contact with methyl- and hydroxyl-terminated self-assembled monolayers (SAM) on gold and gold surfaces regenerated after coagulation were also studied. The regenerated gold surfaces displayed the shortest coagulation times, although the contact-activation of blood coagulation for these surfaces was low. The methylated and hydroxylated surfaces were comparable in terms of coagulation activation, while the hydroxylated surfaces presented FOR signals that indicated detaching of the coagulum from the surface. The combination of SPR and FOR is well suited for studies of cell– and protein–surface interactions and simultaneous bulk processes. Possible applications are investigations of blood cell defects in patients and monitoring of native whole blood interactions with artificial surfaces.

  • 153.
    Hansson, Kenny
    et al.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Vikinge, T. P.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Health Sciences.
    Rånby, M.
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Tengvall, Pentti
    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.
    Johansen, Knut
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Health Sciences.
    Lindahl, Tomas
    Linköping University, Department of Biomedicine and Surgery, Clinical Chemistry. Linköping University, Faculty of Health Sciences.
    Surface plasmon resonance (SPR) analysis of coagulation in whole blood with application in prothrombin time assay1999In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 14, no 8-9, p. 671-682Article in journal (Refereed)
    Abstract [en]

    It is previously shown that surface plasmon resonance (SPR) can be used to study blood plasma coagulation. This work explores the use of this technique for the analysis of tissue factor induced coagulation, i.e. prothrombin time (PT) analysis, of whole blood and plasma. The reference method was nephelometry. The prothrombin time analysis by SPR was performed by mixing two volumes of blood/plasma, one volume of thromboplastin, and one volume of CaCl2 solution directly on a sensor surface. The measurements show good agreement between nephelometry and SPR plasma analysis and also between SPR plasma and whole blood analysis. The effect of anticoagulant treatment on the clotting times was significant both quantitatively and qualitatively. The impact on the SPR signal of different physiological events in the coagulation process is discussed, and tentative interpretations of the sensorgram features are given. The major advantage of the SPR method compared to nephelometry is the possibility to perform analysis on whole blood instead of plasma. In conclusion, SPR is a promising method for whole blood coagulation analysis.

  • 154. Hansson, KM
    et al.
    Vikinge, TP
    Linkoping Univ Hosp, Dept Clin Chem, S-58185 Linkoping, Sweden Linkoping Univ, Forum Scientum Grad Sch, Linkoping, Sweden.
    Ranby, M
    Linkoping Univ Hosp, Dept Clin Chem, S-58185 Linkoping, Sweden Linkoping Univ, Forum Scientum Grad Sch, Linkoping, Sweden.
    Tengvall, Pentti
    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 .
    Lindahl, Tomas
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry.
    Surface plasmon resonance (SPR) analysis of coagulation in whole blood with application in prothrombin time assay1999In: Thrombosis and Haemostasis, ISSN 0340-6245, p. 917-Conference paper (Other academic)
  • 155.
    Hedborg, Eva
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Spetz, Anita
    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.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Polymer membranes for modification of the selectivity of field-effect gas sensors1992In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 7, no 1-3, p. 661-664Article in journal (Refereed)
    Abstract [en]

    Polymer membranes are used to increase the selectivity to certain gases of metal silicon dioxide-semiconductor (MOS) structures. Other parameters which influence the selectivity of MOS structures are the type of gate metal, its microstructure (dense or porous) and the operating temperature of the device. Photoresists as membranes can be patterned by photolithographic methods. Membranes, 1-2-mu-m thick, of positive and negative photoresist are applied on MOS capacitors with 6 nm iridium as the gate metal, operated at 150-degrees-C. The influence of the membranes on the response to three gases, hydrogen, ammonia and ethanol, has been investigated. The hydrogen response decreases bv about half with the use of a photoresist membrane. The ammonia response shows a characteristic change in the kinetics, while the ethanol response almost disappears. Positive and negative resist influence the gas response in similar ways, in spite of their different molecular structures.

  • 156.
    Holmberg, Martin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Gustafsson, Fredrik
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Hörnsten, Gunnar
    SIK, The Swedish Institute for Food and Biotechnology, Ideon Lund.
    Winquist, Fredrik
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Nilsson, Lennart E.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Ljung, Lennart
    Linköping University, Department of Electrical Engineering, Automatic Control. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Bacteria classification based on feature extraction from sensor data1998In: Biotechnology techniques, ISSN 0951-208X, E-ISSN 1573-6784, Vol. 12, no 4, p. 319-324Article in journal (Refereed)
    Abstract [en]

    Data evaluation and classification have been made on measurements by an electronic nose on the headspace of samples of different types of bacteria growing on petri dishes. The chosen groups were: Escherichia coli, Enterococcus sp., Proteus mirabilis, Pseudomonas aeruginosa, and Staphylococcus saprophytica. An approximation of the response curve by time was made and the parameters in the curve fit were taken as important features of the data set. A classification tree was used to extract the most important features. These features were then used in an artificial neural network for classification. Using the ‘leave-one-out’ method for validating the model, a classification rate of 76% was obtained

  • 157.
    Holmin, Susanne
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Krantz-Rülcher, Christina
    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 .
    Winquist, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Drift correction of electronic tongue responses2001In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 12, no 8, p. 1348-1354Article in journal (Refereed)
    Abstract [en]

    In this article, drift correction algorithms were used in order to remove linear drift in multivariate spaces of two data sets obtained by an electronic tongue based on voltammetry. The electronic tongue consisted of various metal electrodes (Au, Ir, Pt, Rh) combined with pattern recognition tools, such as principal component analysis. The first data set contained different types of liquid, from well defined to more complex solutions. The second data set contained different black and green teas. Component correction (CC) was compared to a simple additive correction. In CC, the drift direction of measured reference solutions in a multivariate space was subtracted from other types of solution. In additive correction, responses from reference samples were subtracted from other samples. CC showed similar or better performance in reducing drift compared to additive correction for the two data sets. The additive correction method was dependent on the fact that the differences in between samples of a reference solution were similar to the changes in between samples of other liquids, which was not the case with CC.

  • 158.
    Holub, Douglas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Gifford, Raeann
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Turner, Anthony
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    PoC Amylase Biosensor2014In: 24th Anniversary World Congress on Biosensors – Biosensors 2014, Elsevier, 2014Conference paper (Other academic)
    Abstract [en]

    A rapid, inexpensive and quantitative biosensor to measure alpha-amylase activity within the relevant clinical range has been developed.  This device is suited for point-of-care (PoC) applications because it is easy to use and disposable.  Salivary α-amylase activity is correlated to stress levels and, therefore, it is a potential monitoring candidate for neurological conditions (e.g. Multiple Sclerosis) for which there are no objective diagnostics available.  The enzyme is also utilized in many industrial processes like fermentation and textile production, where real-time, on-site monitoring can be advantageous for accurate process control.  In contrast to other α-amylase quantitative methods, this biosensor is rapid (results within 10 minutes), it does not require bench-top or specialized equipment (i.e. it is portable and does not need to be sent to a laboratory for results), and the general public can perform the analysis (no specialized training needed).  An electro-active moiety, which is sensitive to α-amylase activity, is incorporated into the biosensor design and generates a signal that is proportional to the alpha-amylase activity in the sample (Figure 1, below).  This new device will allow researchers to better diagnose and monitor neurological conditions and follow treatment effectiveness without relying solely on subjective assessments.  In addition, using this novel biosensor to monitor industrial processes that utilize α-amylase could reduce production costs and waste generation for these industries.

  • 159.
    Immerstrand, Charlotte
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Jager, Edwin W.H.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Magnusson, Karl-Eric
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Sundqvist, Tommy
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Peterson, K.H.
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Altered impedance during pigment aggregation in Xenopus laevis melanophores2003In: Medical and Biological Engineering and Computing, ISSN 0140-0118, E-ISSN 1741-0444, Vol. 41, no 3, p. 357-364Article in journal (Refereed)
    Abstract [en]

    Melanophores are dark-brown pigment cells located in the skin of amphibia, fish and many invertebrates. The skin colour of these organisms is regulated by the translocation of pigment organelles, and the pigment distribution can be altered by external stimuli. The ability to change colour in response to stimuli makes these cells of interest for biosensing applications. It was investigated whether pigment aggregation in Xenopus laevis melanophores can be detected by impedance measurements performed in transparent microvials. The results show that cell attachment, cell spreading and pigment aggregation all resulted in impedance changes, seen particularly at the highest frequency tested (10 kHz). The mechanisms behind the impedance changes were investigated by the addition of latrunculin or melatonin, both of which cause pigment aggregation. The latrunculin-induced aggregation was associated with cell area decrease and filamentous actin (F-actin) breakdown, processes that can influence the impedance. Lack of F-actin breakdown and an increase in cell area during melatonin-induced aggregation suggest that some other intracellular process also contributes to the impedance decrease seen for melatonin. It was shown that impedance measurements reflect not only cell attachment and cell spreading, but also intracellular events.

  • 160.
    Ivarsson, Patrik
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Science & Engineering. Asko Cylinder AB.
    Johansson, Madeleine
    Asko Cylinda AB.
    Höjer, Nils-Erik
    Asko Cylinda AB.
    Krantz-Rülcher, Christina
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Winquist, Fredrik
    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.
    Supervision of rinses in a washing machine by a voltammetric electronic tongue2005In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 108, no 01-Feb, p. 851-857Article in journal (Refereed)
    Abstract [en]

    A study that investigates if it is possible to discriminate between the different rinses in a household washing machine with a voltammetric electronic tongue is concluded. The voltammetric electronic tongue applies a potential pulse train over two electrodes and measures the produced current. Multivariate data analysis is used to treat the data. In this paper, a simplified electronic tongue, with only 5% of the original current responses, is used. The rinses from 20 machine wash runs with four different prerequisites are investigated. Principal component analysis (PCA) and Soft-independent modelling of class analogy (SIMCA) are used in order to classify the rinses. In PCA, only one of the rinses is classified erroneous, and in SIMCA none of the rinses are classified only to the wrong class, although 38% of the rinses are classitied to more than one class. (c) 2005 Elsevier B.V. All rights reserved.

  • 161.
    Ivarsson, Patrik
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Science & Engineering. Asko Cylinder AB.
    Kikkawa, Y.
    Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka 812-8581, Japan.
    Winquist, Fredrik
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Krantz-Rülcher, Christina
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Hojer, N.-E.
    Höjer, N.-E., Asko Cylinda AB, SE-534 82 Vara, Sweden.
    Hayashi, K.
    Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka 812-8581, Japan.
    Toko, K.
    Graduate School of Information Science and Electrical Engineering, Kyushu University, Fukuoka 812-8581, Japan.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Comparison of a voltammetric electronic tongue and a lipid membrane taste sensor2001In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 449, no 1-2, p. 59-68Article in journal (Refereed)
    Abstract [en]

    An electronic tongue based on voltammetry and a multichannel lipid membrane taste sensor based on potentiometry are compared using two aqueous examples: detergents and teas. The electronic tongue consists of four electrodes of different metals, a reference electrode and a counter electrode. The measurement principle is based on pulse voltammetry in which current is measured during the change of the amplitude of the applied potential. The taste sensor is based on eight different lipid/polymer membranes. The voltage difference between the electrodes and an Ag/AgCl reference electrode is measured when the current is close to zero. The responses from the two sensors systems are treated separately with multivariate data analysis based on principal component analysis and then merged to examine if further information could be extracted. It is shown that although the two sensor systems are about equal in separation ability in the two cases, extra information can be gained by combination of the two sensor systems. © 2001 Elsevier Science B.V. All rights reserved.

  • 162.
    Ivarsson, Patrik
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Science & Engineering.
    Krantz-Rülcher, Christina
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Winquist, Fredrik
    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.
    A voltammetric electronic tongue2005In: Chemical Senses, ISSN 0379-864X, E-ISSN 1464-3553, Vol. 30, p. I258-i259Article in journal (Refereed)
  • 163.
    Jager, Edwin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Immerstrand, Charlotte
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Magnusson, Karl-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Biomedical applications of polypyrrole microactuators: from single-cell clinic to microrobots2000In: 1st Annual International, Conference On Microtechnologies in Medicine and Biology. 2000, IEEE , 2000, p. 58-61Conference paper (Other academic)
    Abstract [en]

    Microtools that will be useful for the positioning and investigation microstructures must operate relevant environments, such as cell culture media or blood plasma. They must also be comparatively strong, and preferably allow a muscle like mode of movement. This is given by a novel family of actuators based on conjugated polymers (like polypyrrole, PPy). By miniaturising these structures using standard photolithographic techniques, the authors can reduce the size down to 10-micrometer dimensions and build mechanically active microdevices. These can be moved and positioned by applying a potential to dope or undope the PPy. These novel structures are now being developed as a unique microactuator technology, suitable for operation in applications coupled to cell biology and biomedicine

  • 164.
    Jager, Edwin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Inganäs, Olle
    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.
    Microrobots for Micrometer-Size Objects in Aqueous Media: Potential Tools for Single-Cell Manipulation2000In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 288, no 5475, p. 2335-2338Article in journal (Refereed)
    Abstract [en]

    Conducting polymers are excellent materials for actuators that are operated in aqueous media. Microactuators based on polypyrrole-goldbilayers enable large movement of structures attached to theseactuators and are of particular interest for the manipulationof biological objects, such as single cells. A fabrication methodfor creating individually addressable and controllable polypyrrole-goldmicroactuators was developed. With these individually controlledmicroactuators, a micrometer-size manipulator, or microroboticarm, was fabricated. This microrobotic arm can pick up, lift,move, and place micrometer-size objects within an area of about250 micrometers by 100 micrometers, making the microrobot an excellenttool for single-cell manipulation.

  • 165.
    Jager, Edwin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Perpendicular Actuation with Individually Controlled Polymer Microactuators2001In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 13, no 1, p. 76-79Article in journal (Refereed)
    Abstract [en]

    Actuator systems based on conducting polymers, such as polypyrole, with which three-dimensional movement can be controlled, are described. The Figure shows a combination of two such microactuators which are used to “kick” a glass bead across the surface of a silicon wafer. The microfabrication methods used to produce the systems are described and the potential uses, for example microrobotic arms, discussed.

  • 166.
    Jager, Edwin
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Smela, Elisabeth
    Condensed Matter Department, Risö National Lab.
    Inganäs, Olle
    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.
    Polypyrrole micro actuators1999In: Synthetic metals, ISSN 0379-6779, E-ISSN 1879-3290, Vol. 102, no 1-3, p. 1309-1310Article in journal (Refereed)
    Abstract [en]

    The doping and undoping of conjugated polymers is accompanied by a volume change. This volume change can be used to make micro-actuators. We have built polypyrrole (PPy) gold bilayer structures. The volume change of PPy induces a bending of the bilayer. We have made micro-actuators based on this principle, which have been examined with video-microscopy. Some applications for these microactuators are proposed, including opening and closing boxes for cell biology and nanoliter chemistry and micro-robotics.

  • 167.
    Jager, Edwin W.H.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    Immerstrand, Charlotte
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Holmgren Peterson, Kajsa
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, The Institute of Technology.
    The cell clinic: closable microvials for single cell studies2002In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 4, no 3, p. 177-187Article in journal (Refereed)
    Abstract [en]

    We present the development of a cell clinic. This is a micromachined cavity, or microvial, that can be closed with a lid. The lid is activated by two polypyrrole/Au microactuators. Inside the microvials two Au electrodes have been placed in order to perform impedance studies on single or a small number of cells. We report on impedance measurements on Xenopus leavis melanophores. We could measure a change in the impedance upon cell spreading and identify intracellular events such as the aggregation of pigment granules. The electrical data is correlated to optical microscopy.

  • 168. Johansen, K
    et al.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Imaging surface plasmon resonance sensor based on multiple wavelengths: Sensitivity considerations2000In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 71, no 9, p. 3530-3538Article in journal (Refereed)
    Abstract [en]

    A new, multiple wavelength surface plasmon resonance apparatus for imaging applications is presented. It can be used for biosensing, e.g., for monitoring of chemical and biological reactions in real time with label-free molecules. A setup with a fixed incident angle in the Kretschmann configuration with gold as the supporting metal is described, both theoretically and experimentally. Simulations of the sensor response based on independently recorded optical (ellipsometric) data of gold show that the sensitivity for three-dimensional recognition layers (bulk) increases with increasing wavelength. For two-dimensional recognition layers (adlayer) maximum sensitivity is obtained within a limited wavelength range. In this situation, the rejection of bulk disturbances, e.g., emanating from temperature variations, decreases, with increasing wavelength. For imaging surface plasmon resonance the spatial resolution decreases with increasing wavelength. Hence, there is always a compromise between spatial resolution, bulk disturbance rejection, and sensitivity. Most importantly, by simultaneously using multiple wavelengths, it is possible to maintain a high sensitivity and accuracy over a large dynamic range. Furthermore, our simulations show that the sensitivity is independent of the refractive index of the prism. (C) 2000 American Institute of Physics. [S0034-6748(00)02909-9].

  • 169.
    Johansen, Knut
    et al.
    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 .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Sensitivity deviation: Instrumental linearity errors that influence concentration analyses and kinetic evaluation of biomolecular interactions2000In: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 15, no 9-10, p. 503-509Article in journal (Refereed)
    Abstract [en]

    Many scientific instruments utilise multiple element detectors, e.g. CCD's or photodiode arrays, to monitor the change in a position of an optical pattern. For example, instruments for affinity biosensing based on surface plasmon resonance (SPR) or resonant mirror are equipped with such detectors. An important and desired property of these bioanalytical instruments is that the calculation of the movement or change in shape follows the true change. This is often not the case and it may lead to linearity errors, and to sensitivity errors. The sensitivity is normally defined as the slope of the calibration curve. A new parameter is introduced to account for the linearity errors, the sensitivity deviation, defined as the deviation from the undistorted slope of the calibration curve. The linearity error and the sensitivity deviation are intimately related and the sensitivity deviation may lead to misinterpretation of kinetic data, mass transport limitations and concentration analyses. Because the linearity errors are small (e.g. 10 pg/mm2 of biomolecules on the sensor surface) with regard to the dynamic range (e.g. 30 000 pg/mm2), they can be difficult to discover. However, the linearity errors are often not negligible with regard to a typical response (e.g. 0-100 pg/mm2), and may therefore cause serious problems. A method for detecting linearity errors is outlined. Further on, this paper demonstrates how integral linearity errors of less than 1% can result in a sensitivity deviation of 10%, a value that in our opinion cannot be ignored in biospecific interaction analysis (BIA). It should also be stressed out that this phenomenon also occurs in other instruments using array detectors. (C) 2000 Elsevier Science S.A.Many scientific instruments utilize multiple element detectors, e.g. CCD's or photodiode arrays, to monitor the change in a position of an optical pattern. For example, instruments for affinity biosensing based on surface plasmon resonance (SPR) or resonant mirror are equipped with such detectors. An important and desired property of these bioanalytical instruments is that the calculation of the movement or change in shape follows the true change. This is often not the case and it may lead to linearity errors, and to sensitivity errors. The sensitivity is normally defined as the slope of the calibration curve. A new parameter is introduced to account for the linearity errors, the sensitivity deviation, defined as the deviation from the undistorted slope of the calibration curve. The linearity error and the sensitivity deviation are intimately related and the sensitivity deviation may lead to misinterpretation of kinetic data, mass transport limitations and concentration analyses. Because the linearity errors are small (e.g. 10 pg/mm2 of biomolecules on the sensor surface) with regard to the dynamic range (e.g. 30 000 pg/mm2), they can be difficult to discover. However, the linearity errors are often not negligible with regard to a typical response (e.g. 0-100 pg/mm2), and may therefore cause serious problems. A method for detecting linearity errors is outlined. Further on, this paper demonstrates how integral linearity errors of less than 1% can result in a sensitivity deviation of 10%, a value that in our opinion cannot be ignored in biospecific interaction analysis (BIA). It should also be stressed out that this phenomenon also occurs in other instruments using array detectors.

  • 170.
    Johansen, Knut
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Stalberg, R.
    Stålberg, R., Høgskolen i Telemark, Hallvard Eikas plass, 3800 Bø, Norway.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Surface plasmon resonance: Instrumental resolution using photo diode arrays2000In: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 11, no 11, p. 1630-1638Article in journal (Refereed)
    Abstract [en]

    Surface plasmon resonance (SPR) sensors are used to study biomolecular interactions. We have performed a theoretical analysis of a SPR instrument using a convergent beam, a linear detector with various numbers of pixels and various analogue-to-digital converters (ADCs) with a corresponding resolution ranging from 8 to 16 bits. Studies of small molecules at low concentrations or with low affinities are limited by the instrumental set-up, e.g. by the resolution, linearity and noise. The amplitudes of these parameters are highly dependent on the detector, ADC and dip-finding algorithm used. We have studied several dip-finding algorithms, e.g. intensity measurements, second- and third-order polynomial fits and centroid algorithms. Each algorithm used with the ADC and the detector has a resolution associated with it. Some algorithms also have an intrinsic algorithm error that is dependent on the number of pixels and the shape of the dip. A weighted centroid algorithm that has an excellent overall performance is described. If an accuracy of 10-6 refractive index units (RIU) is satisfactory, a 12-bit ADC and a 64-pixel detector are appropriate. Theoretically, by using a 16-bit ADC and a 1024-pixel detector, a resolution of better than 10-9 RIU is obtainable.

  • 171.
    Johansson, Fredrik
    et al.
    Linköping University, Department of Medicine and Care, Pharmacology. Linköping University, Faculty of Health Sciences.
    Andersson, Tony P. M.
    Linköping University, Department of Medicine and Care, Pharmacology. Linköping University, Faculty of Health Sciences.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, Faculty of Health Sciences.
    Svensson, Samuel P. S.
    Linköping University, Department of Medicine and Care, Pharmacology. Linköping University, Faculty of Health Sciences.
    Is effect of (S;S)-formoterol due to contamination of (R;R)-formoterol?Manuscript (preprint) (Other academic)
    Abstract [en]

    Formoterol is a long acting selective ß2-adrenoceptor (ß2-AR) agonist of the so-called third generation of ß-adrenoceptor agonists. lt also has an onset action comparable to most short acting ß2-AR agonists. Formoterol has two chiral centres making four enantiomers possible. In this study we have examined (R;R)- and (S;S)-formoterol relaxing effect on guinea pig tracheal ring preparations, affinity to human ß2-AR in transfected COS-7 cells and the ability to influence pigment movement in frog melanophores with stable expression of human ß2AR. We also compared single concentration curves versus cumulative concentration curves on guinea pig tracheal preparations. In all three systems the (R;R)-formoterol is the most potent ß2AR agonist compered to (S;S)-formoterol with eudismic ratios ranging from 11 to 75. We also measure and theoretically calculated the effect of (S;S)-formoterol. VVhen the contamination of (R;R)-formoterol was subtracted the (S;S)-formoterol had effect, although approximately 72 times less then (R;R)-formoterol. We conclude that (R;R)-formoterol is the most potent ß2-AR agonist in three different systems and that (S;S)-formoterol posses an ß2-AR effect. We also show that cumulative concentration curves have higher EC50 values compered to single concentration curves and that this might be a consequence of recaptor desensitisation.

  • 172. Johansson, M
    et al.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Ekedahl, Lars-Gunnar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    An equipment for three-dimensional spatially resolved gas analysis2000In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 71, no 9, p. 3513-3521Article in journal (Refereed)
    Abstract [en]

    The apparatus described is able to measure three-dimensional temperature and partial pressure distributions in gas mixtures with a spatial resolution better than 0.5 mm. The measurements are performed in a well defined laminar gas flow in a duct of rectangular cross section. The gas mixture is sampled locally with a quartz tube orifice leak movable in three dimensions. Mass spectrometry is used for partial pressure measurements. The total pressure in the duct can be regulated in the range 50-760 Torr and the gas temperature can be varied between room temperature and 500 degrees C. The apparatus is primarily designed for studies of the distribution of reactants and products over catalytic surfaces. Because of the well defined gas flow in the duct the partial pressure distributions of reactants and products over the catalytic surface can be calculated with good accuracy. By comparing calculated pressure distributions to measured ones the local reaction rate on the catalytic surface as well as the pressures of reactants and products at the surface can be obtained. As an example it is shown how the hydrogen distribution over a platinum surface exposed to a mixture of hydrogen, oxygen, and argon can be used to calculate the local water formation rate on the platinum surface. (C) 2000 American Institute of Physics. [S0034-6748(00)01409-X].

  • 173.
    Kalli, K.
    et al.
    University of Cyprus, Nicosia.
    Othonos, A.
    University of Cyprus, Nicosia.
    Christofides, C.
    University of Cyprus, Nicosia.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Room temperature hydrogen gas detection with optically thin palladium films on silicon oxide using photomodulated thermoreflectance1999In: AIP Conference Proceedings, ISSN 0094-243X, E-ISSN 1551-7616, Vol. 463, p. 220-222Article in journal (Refereed)
    Abstract [en]

    The sensitivity of various thicknesses of optically thin film Pd layers evaporated into a silicon oxide substrate is investigated in the presence of a hydrogen/air atmosphere at room temperature. The magnitude of the resulting reflectivity change is measured using an excite-probe technique, through laser excited photothermal modulation of a probe beam. Data indicates that concentrations of 0.1% hydrogen in a balanced air mixture and at room temperature may be measured with. an 8nm Pd film. Inhomogeneities in the Pd layers lead to anomalous behavior.

  • 174.
    Kalli, K
    et al.
    University of Cyprus, Cyprus.
    Othonos, A
    University of Cyprus, Cyprus.
    Christofides, C
    University of Cyprus, Cyprus.
    Lloyd Spetz, Anita
    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, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Temperature-induced reflectivity changes and activation of hydrogen sensitive optically thin palladium films on silicon oxide1998In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 69, no 9, p. 3331-3338Article in journal (Refereed)
    Abstract [en]

    The optical properties of several thin metal film palladium-silicon oxide structures are examined at room temperature before and after annealing to 200 degrees C and also at 90 degrees C-in all cases in the presence of hydrogen gas. Multicycling sample activation is shown to occur iii the presence of hydrogen at room temperature with an increase in reflectivity on exposure to hydrogen, in contrast to thicker 80 Angstrom films. The reflectivity change increases with increasing film thickness (1-10 Angstrom). The surface activation at room temperature, before and after annealing to 200 degrees C, is compared with the performance at 90 degrees C, where it is shown that heat treatment strongly influences the behavior of the metal film.

  • 175. Kalman, E.-L.
    et al.
    Lofvendahl, A.
    Löfvendahl, A., Volvo Car Corporation, 98351 PV 1B, S-405 08, Göteborg, Sweden.
    Winquist, Fredrik
    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 .
    Classification of complex gas mixtures from automotive leather using an electronic nose2000In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 403, no 1-2, p. 31-38Article in journal (Refereed)
    Abstract [en]

    A semiconductor gas sensor array combined with a routine for pattern recognition - a so-called electronic nose - for the detection of gas emissions from the leather used in car compartments is described. The gas sensors are 10 metal oxide semiconductor field effect transistors (MOSFETs) with gates of thin, catalytic metals, and five semiconducting metal oxide sensors. The sensor array data are processed by multivariate means using principal component analysis (PCA) and are shown to give similar and add additional information compared to gas chromatography-mass spectrometry (GC- MS) and a human sensory panel. The total volatile organic compound concentration as measured by GC did not differ between good and bad samples and could therefore not be used as a quality control tool, whilst the electronic nose together with pattern recognition could readily discover the deviating samples with unusual emitting gases. This set-up could be useful in on-line quality monitoring systems to detect anomalies in incoming car interior trim materials.

  • 176.
    Karlsson, Annika M.
    et al.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Bjuhr, Katarina
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Testorf, Martin
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Öberg, Åke
    Linköping University, Department of Biomedical Engineering, Physiological Measurements. Linköping University, The Institute of Technology.
    Lerner, Ethan
    Bunsen Rush Laboratories, Dallas, TX, USA.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Svensson, Samuel P.S.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Biosensing of opioids using frog melanophores2002In: Biosensors and Bioelectronics, ISSN 0956-5663, Vol. 17, no 4, p. 331-335Article in journal (Refereed)
    Abstract [en]

    Spectacular color changes of fishes, frogs and other lower vertebrates are due to the motile activities of specialized pigment containing cells. Pigment cells are interesting for biosensing purposes since they provide an easily monitored physiological phenomenon. Melanophores, containing dark brown melanin pigment granules, constitute an important class of chromatophores. Their melanin-filled pigment granules may be stimulated to undergo rapid dispersion throughout the melanophores (cells appear dark), or aggregation to the center of the melanophores (cells appear light). This simple physiological response can easily be measured in a photometer. Selected G protein coupled receptors can be functionally expressed in cultured frog melanophores. Here, we demonstrate the use of recombinant frog melanophores as a biosensor for the detection of opioids. Melanophores were transfected with the human opioid receptor 3 and used for opiate detection. The response to the opioid receptor agonist morphine and a synthetic opioid peptide was analyzed by absorbance readings in an aggregation assay. It was shown that both agonists caused aggregation of pigment granules in the melanophores, and the cells appeared lighter. The pharmacology of the expressed receptors was very similar to its mammalian counterpart, as evidenced by competitive inhibition by increasing concentrations of the opioid receptor inhibitor naloxone. Transfection of melanophores with selected receptors enables the creation of numerous melanophore biosensors, which respond selectively to certain substances. The melanophore biosensor has potential use for measurement of substances in body fluids such as saliva, blood plasma and urine.

  • 177.
    Karlsson, Annika M.
    et al.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Lerner, Michael R.
    Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
    Unett, David
    Department of Dermatology, University of Texas Southwestern Medical Center, Dallas, TX, USA.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Svensson, Samuel P.S.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Melatonin-induced organelle movement in melanophores is coupled to tyrosine phosphorylation of a high molecularweight protein2000In: Cellular signalling, ISSN 0898-6568, Vol. 12, no 7, p. 469-474Article in journal (Refereed)
    Abstract [en]

    Melanophores, brown to black pigment cells from, for example, Xenopus laevis, contain mobile melanin filled organelles, and are well suited for studies on organelle movement. The intracellular regulation of the movement seems to be controlled by serine and threonine phosphorylations and dephosphorylations. Melatonin induces aggregation of the melanosomes to the cell centre through a Gi/o-protein-coupled receptor, Mel1c, which leads to an inhibition of PKA and a stimulation of PP2A. However, this study shows that the melatonin-induced aggregation of melanosomes is also accompanied by tyrosine phosphorylation of a protein with a molecular weight of 280 kDa. Cells pre-incubated with genistein, an inhibitor of tyrosine phosphorylations, showed inhibited melanosome movement after melatonin stimulation, and a lower degree of tyrosine phosphorylation of the 280 kDa protein. The adenylyl cyclase activator forskolin, and the Gi/o protein inhibitor pertussis toxin, also inhibited tyrosine phosphorylation of the 280 kDa protein. The results indicate that melatonin stimulation generates tyrosine phosphorylation of a high molecular weight protein, an event that seems to be essential for melanosome aggregation.

  • 178.
    Karlsson, Jan Olof G
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Ignarro, Louis J
    Department of Molecular and Medical Pharmacology, University of California, USA.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Biosensors and Bioelectronics. Linköping University, Faculty of Science & Engineering.
    Jynge, Per
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences.
    Almén, Torsten
    Department of Diagnostic Radiology, Lund University.
    Calmangafodipir [Ca4Mn(DPDP)5], mangafodipir (MnDPDP) and MnPLED with special reference to their SOD mimetic and therapeutic properties2015In: Drug Discovery Today, ISSN 1359-6446, E-ISSN 1878-5832, Vol. 20, no 4, p. 411-421Article, review/survey (Refereed)
    Abstract [en]

    Reactive oxygen species (ROS) and reactive nitrogen species (RNS) participate in pathological tissue damage. Mitochondrial manganese superoxide dismutase (MnSOD) normally keeps ROS and RNS in check. During development of mangafodipir (MnDPDP) as a magnetic resonance imaging (MRI) contrast agent, it was discovered that MnDPDP and its metabolite manganese pyridoxyl ethyldiamine (MnPLED) possessed SOD mimetic activity. MnDPDP has been tested as a chemotherapy adjunct in cancer patients and as an adjunct to percutaneous coronary intervention in patients with myocardial infarctions, with promising results. Whereas MRI contrast depends on release of Mn2+, the SOD mimetic activity depends on Mn2+ that remains bound to DPDP or PLED. Calmangafodipir [Ca4Mn(DPDP)5] is stabilized with respect to Mn2+ and has superior therapeutic activity. Ca4Mn(DPDP)5 is presently being explored as a chemotherapy adjunct in a clinical multicenter Phase II study in patients with metastatic colorectal cancer.

  • 179.
    Karlsson, Jan Olof
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Jynge, Per
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Sensor and Actuator Systems. Linköping University, Faculty of Science & Engineering.
    Ignarro, Louis J.
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Pharmacology.
    Letter in response to: "Randomised open label exploratory, safety and tolerability study with calmangafodipir in patients treated with the 12-h regimen of N acetylcysteine for paracetamol overdosethe PP100-01 for Overdose of Paracetamol (POP) trial: study protocol for a randomised controlled trial"2019In: Trials, ISSN 1745-6215, E-ISSN 1745-6215, Vol. 20, article id 380Article in journal (Other academic)
    Abstract [en]

    n/a

  • 180.
    Karlsson, L M
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Tengvall, Pentti
    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.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Adsorption of human serum albumin in porous silicon gradients2003Conference paper (Other academic)
    Abstract [en]

    Backside etching has been utilized to produce gradients of pore size and layer thickness in porous silicon. Human serum albumin (HSA) was adsorbed on such gradients at two different pH values: 4.9, the pI of HSA, and 7.4, the physiological pH. The samples were investigated by scanning electron microscopy, spectroscopic ellipsometry, and autoradiography. The results show that the protein adsorbed displays a gradient along with the pore size and the thickness gradient. The higher than current density used during etching, the more sway-back shaped curves were seen for the protein adsorption pattern, independent of pH. When 50 mA/cm2 current density was used during etching, the quota between the maximal intensity value and the plateau value seen after adsorption of the HSA increased for pH 7.4.

  • 181.
    Karlsson, L M
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Tengvall, Pentti
    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.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Back-side etching A tool for making morphology gradients in porous silicon2002In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 149, no 12Article in journal (Refereed)
    Abstract [en]

    A new method for preparing morphology gradients in electrochemically etched porous silicon layers in presented. The idea is to etch on the back side of the anode and thus utilize and inhomogenous electric field to control the pore size along a surface. The etching procedure resulted in a complex gradient in pore size, porosity, and porous layer thickness, which was studied by spectroscopic ellipsometry and scanning electron microscopy. The gradients are of interest, e.g., for biomaterials research, bio-sensor applications, and for basic studies of adsorption of organic molecules, like proteins. In order to investigate the potential of the gradient surfaces for protein adsorption studies, these were exposed to human serum albumin, and a gradient in the amount of adsorbed protein was observed.

  • 182.
    Karlsson, L M
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Tengvall, Pentti
    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.
    Arwin, Hans
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Optics .
    Penetration and loading of human serum albumin in porous silicon layers with different pore sizes and thicknesses2003In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 266, no 1, p. 40-47Article in journal (Refereed)
    Abstract [en]

    Human serum albumin was adsorbed into porous silicon layers with thickness up to 3 µm and with different mean pore radius in the range 4.5-10 nm. The adsorbed amount of protein was quantified by I125 radioactive labeling techniques and ellipsometry. The results show that albumin penetrated into the pores when the mean pore radius was larger than 5.5 nm, but could not totally occupy the available surface area when the layer thickness was larger than 1 µm. Loading of albumin both into porous layers and onto plane silicon as a function of albumin concentration was also investigated. These measurements show that loading of protein increased with protein concentration at least up to 10 mg/ml for porous silicon and up to 1 mg/ml for plane silicon. The maximum deposition into the type of porous layers used here was 28 µg/cm2, compared to 0.36 µg/cm2 for plane silicon. © 2003 Elsevier Inc. All rights reserved.

  • 183.
    Karlsteen, M.
    et al.
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Baranzahi, Amir
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lloyd Spetz, Anita
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Willander, Magnus
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Electrical properties of inhomogeneous SiC MIS structures1995In: Journal of Electronic Materials, ISSN 0361-5235, E-ISSN 1543-186X, Vol. 24, no 7, p. 853-861Article in journal (Refereed)
    Abstract [en]

    Current-voltage characteristics of metal contacts on 6H-SiC with a thin (5-20 Angstrom) oxide layer have been measured in the temperature range 300 to 1000K. The contacts were investigated in both H-2 and O-2-atmospheres. As the SiC surface was nonideal due to pin holes and other defects generated during the growth process, it was necessary to treat the Schottky contacts as inhomogeneous contacts. The inhomogeneity explains the nonideal current-voltage behavior of the contacts such as ideality factors much larger than unity and voltage dependent ideality factors. It was found that some metals gave Schottky contacts in the entire temperature range, while other metals were ohmic at higher temperatures. Several different contact metals were investigated: Al, Ti, TaSix, and Pd were found to be ohmic at high temperatures, while Pt, Pt+Cr, Ni, Cr and another TaSix contact were found to behave like Schottky contacts in the entire temperature range. This is a preliminary investigation of the electrical characteristics of different metals that could be useful for high temperature gas sensor purposes.

  • 184.
    Klenkar, Goran
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Valiokas, Ramunas
    IFM .
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Tinazli, A.
    Tampé, R.
    Piehler, J.
    Liedberg, Bo
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics .
    Micro-fabricated array chips based on multivalent chelating thiols: production, characterization and application2006Other (Other (popular science, discussion, etc.))
    Abstract [en]

    Posterbidrag på Biosensors 2006 kongress, Toronto, Kanada, 10-12 maj

  • 185.
    Klenkar, Goran
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Valiokas, Ramunas
    Molecular Compounds Physics Laboratory, Institute of Physics, Vilnius, Lithuania.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics . Linköping University, The Institute of Technology.
    Tinazli, Ali
    Institute of Biochemistry, Johann Wolfgang Goethe-University, Frankfurt, Germany.
    Tampé, Robert
    Institute of Biochemistry, Johann Wolfgang Goethe-University, Frankfurt, Germany.
    Piehler, Jacob
    Institute of Biochemistry, Johann Wolfgang Goethe-University, Frankfurt, Germany.
    Liedberg, Bo
    Linköping University, Department of Physics, Chemistry and Biology, Sensor Science and Molecular Physics . Linköping University, The Institute of Technology.
    Piezo Dispensed Microarray of Multivalent Chelating Thiols for Dissecting Complex Protein-Protein Interactions2006In: Analytical Chemistry, ISSN 0003-2700, Vol. 78, no 11, p. 3643-3650Article in journal (Refereed)
    Abstract [en]

    The fabrication of a novel biochip, designed for dissection of multiprotein complex formation, is reported. An array of metal chelators has been produced by piezo dispensing of a bis-nitrilotriacetic acid (bis-NTA) thiol on evaporated gold thin films, prestructured with a microcontact printed grid of eicosanethiols. The bis-NTA thiol is mixed in various proportions with an inert, tri(ethylene glycol) hexadecane thiol, and the thickness and morphological homogeneity of the dispensed layers are characterized by imaging ellipsometry before and after back-filling with the same inert thiol and subsequent rinsing. It is found that the dispensed areas display a monotonic increase in thickness with increasing molar fraction of bis-NTA in the dispensing solution, and they are consistently a few Ångströms thicker than those prepared at the same molar fraction by solution self-assembly under equilibrium-like conditions. The bulkiness of the bis-NTA tail group and the short period of time available for chemisorption and in-plane organization of the dispensed thiols are most likely responsible for the observed difference in thickness. Moreover, the functional properties of this biochip are demonstrated by studying multiple protein−protein interactions using imaging surface plasmon resonance. The subunits of the type I interferon receptor are immobilized as a composition array determined by the surface concentration of bis-NTA in the array elements. Ligand dissociation kinetics depends on the receptor surface concentration, which is ascribed to the formation of a ternary complex by simultaneous interaction of the ligand with the two receptor subunits. Thus, multiplexed monitoring of binding phenomena at various compositions (receptor densities) offers a powerful tool to dissect protein−protein interactions.

  • 186.
    Klingvall, Roger
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Eriksson, Mats
    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 .
    SLPT studies of a MISiC device2005In: IEEE Sensors 2005,2005, 2005Conference paper (Refereed)
  • 187.
    Klingvall, Roger
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Eriksson, Mats
    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 .
    UV-SLPT for gas sensor research on MISiC devices2007In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 7, no 03-Apr, p. 592-599Article in journal (Refereed)
    Abstract [en]

    A modified Scanning Light Pulse Technique (SLPT) setup that can be used to evaluate SiC-based gas-sensitive field-effect devices is introduced. This is exemplified with measurements on a Pt-MISiC capacitor that has a metal thickness gradient. The device shows large responses to hydrogen and ammonia in air. The H-2 and NH3 responses show a complementary dependence on the Pt film thickness at 140 degrees C. The temperature dependence differs however for the two gases. The measurement setup uses UV transparent optics together with mechanical chopping of light from a short wavelength light source. The spatial resolution of the system is found to be approximately 50 mu m.

  • 188.
    Klingvall, Roger
    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, Biosensors and Bioelectronics. Linköping University, The Institute of Technology.
    Eriksson, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Robust gas detection at sub ppm concentrations2011In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 160, no 1, p. 571-579Article in journal (Refereed)
    Abstract [en]

    Gas sensors often suffer from signal drift and long response and recovery times, giving rise to problems to evaluate the steady state gas response. It is shown that these problems can be reduced by modulating the test gas concentration and utilizing the change in the slope of the sensor signal as the sensor response feature. The case of low hydrogen concentration detection is studied using a light pulse technique and a PdPt-MIS field-effect device. For the difference in slope method it was possible to reduce the measurement time from hours in the steady state measurements to 1 + 1 min (test gas + reference gas exposure time) and still achieve a detection limit of about 40 ppb for a step change in hydrogen concentration. Such measurements could be made in spite of a drifting baseline caused, e.g. by previous hydrogen exposures. A theoretical model of how a step change in the hydrogen partial pressure affects the difference in slope is given. The model also predicts a non-reactive hydrogen sticking probability (i.e. the probability that an incoming hydrogen molecule from the gas phase will contribute to the response) of about 1 x 10(-8) at 100 ppb H(2), which is about 2 orders of magnitude lower than the reactive sticking coefficient. (C) 2011 Elsevier B.V. All rights reserved.

  • 189.
    Klingvall, Roger
    et al.
    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 .
    Eriksson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Sub ppm detection of hydrogen2008In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 8, no 03-Apr, p. 301-307Article in journal (Refereed)
    Abstract [en]

    A light pulse technique and a field-effect device were used to detect small concentration steps of hydrogen in air. The detection limit was lower than 40 ppb, which is at least one order of magnitude lower than previously reported measurements (with field-effect devices) of hydrogen concentration in air. The device structure was a metal-insulator-semiconductor capacitor with a metal double layer with 17.5 nm Pd (upper layer) and 7.5 nm Pt on a SiO2 insulator and a Si substrate.

  • 190.
    Klingvall, Roger
    et al.
    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 .
    Löfdahl, Mikael
    AppliedSensor AB.
    Eriksson, Mats
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    A combinatorial approach for field-effect gas sensor research and development2005In: IEEE Sensors Journal, ISSN 1530-437X, E-ISSN 1558-1748, Vol. 5, no 5, p. 995-1003Article in journal (Refereed)
  • 191.
    Krantz-Rülcher, Christina
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Stenberg, M.
    Winquist, Fredrik
    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 .
    Electronic tongues for environmental monitoring based on sensor arrays and pattern recognition: A review2001In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 426, no 2, p. 217-226Conference paper (Other academic)
    Abstract [en]

    The use of sensor arrays and pattern recognition applied to the obtained signal patterns for environmental monitoring are discussed in some detail. Different types of electronic tongues are described and evaluated for monitoring purposes. More specifically the performance of multielectrode arrays used for voltammetric analysis of aqueous samples is described. It is, e.g. shown how such an 'electronic tongue' can be used to monitor the quality of water in a production plant for drinking water. It is pointed out that the concepts of 'electronic noses' and 'electronic tongues' often predict a quality of a sample rather than giving exact information about concentrations of individual species. (C) 2001 Elsevier Science B.V.

  • 192.
    Linnarsson, MK
    et al.
    Royal Inst Technol, SE-16440 Kista, Sweden Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden ACREO, SE-16440 Kista, Sweden.
    Lloyd-Spets, Anita
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Janson, MS
    Ekedahl, Lars-Gunnar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Karlsson, S
    Schoner, A
    Royal Inst Technol, SE-16440 Kista, Sweden Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden ACREO, SE-16440 Kista, Sweden.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Svensson, BG
    Metal-contact enhanced incorporation of deuterium in 4H-and 6H-SiC2000In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 338-3, p. 937-940Article in journal (Refereed)
    Abstract [en]

    Deuterium was introduced in p-type SiC from a gas ambient. The samples were partially coated with 200 Angstrom thick metal layer of titanium, nickel, platinum or gold. Heat treatments were performed in the temperature range 500-800 degreesC during 4 h. Secondary ion mass spectrometry (SIMS) was used to measure the deuterium content after deuterium exposure. The catalytic metal coating is shown to play an important role for introducing deuterium into SiC. Nickel and platinum facilitate hydrogen incorporation in p-type SiC, which may be due to an increased hydrogen concentration at the metal/SiC interface and/or an increase the H+ ions to H ratio. No in-diffusion of deuterium is observed using titanium although large quantities of deuterium are stored in the titanium film. Furthermore, gold reveals an inert character and does not promote in-diffusion of deuterium.

  • 193.
    Lloyd Spetz, Anita
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Baranzahi, Amir
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Tobias, Peter
    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.
    High temperature sensors based on metal-insulator-silicon carbide devices1997In: Physica status solidi. A, Applied research, ISSN 0031-8965, E-ISSN 1521-396X, Vol. 162, no 1, p. 493-511Article in journal (Refereed)
    Abstract [en]

    High temperature gas sensors based on catalytic metal-insulator-silicon carbide (MISiC) devices are developed both as capacitors and Schottky diodes. A maximum operation temperature of 1000 degrees C is obtained for capacitors based on 4H-SiC, and all sensors work routinely for several weeks at 600 degrees C. Reducing gases like hydrocarbons and hydrogen lower the flat band voltage of the capacitor and the barrier height of the diode. The time constants for the gas response are in the order of milliseconds and because of this good performance the sensors are tested for combustion engine control. For temperatures around 600 degrees C total combustion occurs on the sensor surface and the signal is high for fuel in excess and low for air in excess. At temperatures around 400 degrees C the response is more linear. The high temperature operation causes interdiffusion of the metal and insulator layers in these devices; and this interdiffusion has been studied. At sufficiently high temperatures the inversion capacitance shows different levels for hydrogen free and hydrogen containing ambients, which is suggested to be due to a reversible hydrogen annealing effect at the insulator-silicon carbide interface.

  • 194.
    Lloyd Spetz, Anita
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Schmeisser, D.
    Technische Universitaet Cottbus, Germany.
    Baranzahi, Amir
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Wälivaara, B.
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    Göpel, W.
    Institut für Physikalische und Theoretische Chemie, Tübingen, Germany.
    Lundström, Ingemar
    Linköping University, Department of Physics, Chemistry and Biology, Applied Physics. Linköping University, The Institute of Technology.
    X-ray photoemission and Auger electron spectroscopy analysis of fast responding activated metal oxide silicon carbide gas sensors1997In: Thin Solid Films, ISSN 0040-6090, E-ISSN 1879-2731, Vol. 299, no 1-2, p. 183-189Article in journal (Refereed)
    Abstract [en]

    Platinum-silicon dioxide-silicon carbide, MOSiC, sensors are possible to operate at high temperatures and show a gas sensitivity pattern which is of interest for many applications including exhaust gases from car engines. The introduction of a buffer layer of tantalum silicide between the metal and the silicon dioxide resulted, after an annealing step, in a very good adhesion of the gate contact and fast responding sensors with improved signal stability. Depth profiling using X-ray photoemission and Auger electron spectroscopy showed that the annealing step converts the tantalum silicide to a mixed phase predominantly containing tantalum pentoxide. Tantalum silicide as well as platinum silicide are also present in the metal-oxide interface region.

  • 195.
    Lloyd-Spets, Anita
    et al.
    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 .
    di Natale, C.
    Buchholt, Krisitina
    IFM .
    Martinelli, E.
    DAmico, A.
    Paolesse, R.
    Investigation of the selectivity properties of metalloporphyrines self-assembled-monolayers on QMB and FET transducers2006In: Proc. Eurosensors XX,2006, 2006Conference paper (Refereed)
    Abstract [en]

       

  • 196.
    Lloyd-Spets, Anita
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Tobias, P
    Linkoping Univ, S SENCE, S-58183 Linkoping, Sweden Linkoping Univ, Appl Phys Lab, S-58183 Linkoping, Sweden.
    Baranzahi, A
    Martensson, P
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics.
    Current status of silicon carbide based high-temperature gas sensors1999In: IEEE Transactions on Electron Devices, ISSN 0018-9383, E-ISSN 1557-9646, Vol. 46, no 3, p. 561-566Article in journal (Refereed)
    Abstract [en]

    Silicon carbide (SIC) based field effect gas sensors can be operated at very high temperatures. Catalytic metal-insulator-silicon carbide (MISiC) Schottky diodes respond very fast to a change between a reducing and an oxidizing atmosphere, and cylinder-specific combustion engine monitoring has been demonstrated. The sensors have also been suggested for high-temperature electronic nose applications. Car applications and other harsh environments put very strong requirements on the long-term stability of the sensors. Here rye review the current status of the field of SiC based Schottkg diode gas sensors with emphasis on the work in our group. Basic work on understanding of the detection mechanism and the influence of interfacial layers on the long-term stability of the sensors is reviewed, The direction of future research and device development in our group is also discussed.

  • 197.
    Lloyd-Spets, Anita
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Tobias, P.
    Unéus, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Svenningstorp, H.
    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 .
    High temperature catalytic metal field effect transistor for industrial applications2000In: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 70, no 1-3, p. 67-76Article in journal (Refereed)
    Abstract [en]

    Field effect chemical sensors, utilising silicon carbide as semiconductor, can be operated at high temperature and in rough environments. Gas sensitive field effect transistors, MISiCFET, are now developed (ACREO, Kista in Sweden). This will increase the number of possible applications for field effect gas sensors. The first batch of MISiCFET devices is possible to operate in intermittent pulses of hydrogen/oxygen up to 775°C. At temperature above 600°C, the gas response of the MISiC devices has very short time constants for a change between oxidising and reducing atmosphere and cylinder specific monitoring of a combustion engine has been demonstrated. Other industrial applications, like exhaust diagnosis and flue gas monitoring, have been demonstrated by the use of MISiC Schottky diodes at lower temperatures, 200°C-500°C.

  • 198.
    Lloyd-Spets, Anita
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Unéus, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Svenningstorp, H
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Tobias, P
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Ekedahl, Lars-Gunnar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology.
    Larsson, O
    Goras, A
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Savage, S
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Harris, C
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Martensson, P
    Wigren, R
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Salomonsson, P
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Haggendahl, B
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Ljung, P
    Mattsson, M
    Linkoping Univ, S SENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Medel AB, SE-66222 Amal, Sweden ABREO AB, SE-16440 Kista, Sweden Appl Sensor, SE-58330 Linkoping, Sweden Volvo TU, SE-41288 Gothenburg, Sweden Vattenfall Utveckling, SE-81426 Alvkarleby, Sweden.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    SiC based field effect gas sensors for industrial applications2001In: Physica status solidi. A, Applied research, ISSN 0031-8965, E-ISSN 1521-396X, Vol. 185, no 1, p. 15-25Article in journal (Refereed)
    Abstract [en]

    The development and field-testing of high-temperature sensors based on silicon carbide devices have shown promising results in several application areas. Silicon carbide based field-effect sensors can be operated over a large temperature range, 100-600 degreesC, and since silicon carbide is a chemically very inert material these sensors can be used in environments like exhaust gases and flue gases from boilers. The sensors respond to reducing gases like hydrogen, hydrocarbons and carbon monoxide. The use of different temperatures, different catalytic metals and different structures of the gate metal gives selectivity to different gases and arrays of sensors can be used to identify and monitor several components in gas mixtures. MOSFET sensors based on SIC combine the advantage of simple circuitry with a thicker insulator, which increases the long term stability of the devices. In this paper we describe silicon carbide MOSFET sensors and their performance and give: examples of industrial applications such as monitoring of car exhausts and flue gases. Chemometric methods have been used for the evaluation of the data.

  • 199.
    Lloyd-Spets, Anita
    et al.
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Unéus, Lars
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Svenningstorp, H
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Wingbrant, Helena
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Harris, CI
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Salomonsson, P
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Tengstrom, P
    Martensson, P
    Ljung, P
    Mattsson, M
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Visser, JH
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Ejakov, SG
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    Kubinski, D
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    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 .
    Savage, SM
    SSENCE, SE-58183 Linkoping, Sweden Linkoping Univ, Div Appl Phys, SE-58183 Linkoping, Sweden Ford Motor Co, Dearborn, MI 48124 USA Vattenfall Dev, SE-81426 Alvkarleby, Sweden AppliedSensor AB, SE-58330 Linkoping, Sweden Volvo PV AB, SE-40508 Gothenburg, Sweden ACREO Ab, SE-16440 Kista, Sweden Volvo TU, SE-41288 Gothenburg, Sweden.
    MISiCFET chemical gas sensors for high temperature and corrosive environment applications2002In: Materials Science Forum, ISSN 0255-5476, E-ISSN 1662-9752, Vol. 389-3, p. 1415-1418Article in journal (Refereed)
    Abstract [en]

    A chemical gas sensor based on a silicon carbide field effect transistor with a catalytic gate metal has been under development for a number of years. The buried gate design allows the sensor to operate at high temperatures, routinely up to 600degreesC and for at least three days at 700degreesC. The chemical inertness of silicon carbide makes it a suitable sensor technology for applications in corrosive environments such as exhaust gases and flue gases from boilers. The selectivity of the sensor devices is established through the choice of type and structure of the gate metal as well as the operation temperature. In this way NH3 sensors with low cross sensitivity to NOx have been demonstrated as potential sensors for control of selective catalytic reduction (SCR) of NOx by urea injection into diesel exhausts. The hardness of the silicon carbide makes it for example more resistant to water splash at cold start of a petrol engine than existing technologies, and a sensor which can control the air to fuel ratio, before the exhaust gases are heated, has been demonstrated. Silicon carbide sensors are also tested in flue gases from boilers. Efficient regulation of the combustion in a boiler will decrease fuel consumption and reduce emissions.

  • 200.
    Lundström, Ingemar
    Linköping University, The Institute of Technology. Linköping University, Department of Physics, Chemistry and Biology, Applied Physics .
    Artificial noses: Picture the smell2000In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 406, no 6797, p. 682-683Article, review/survey (Refereed)
    Abstract [en]

    [No abstract available]

1234567 151 - 200 of 328
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • oxford
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf