A novel biochip technology for detection of explosives - TNT: Synthesis, characterisation and application
2006 (English)In: Sensors and Actuators B: Chemical, ISSN 0925-4005, Vol. 113, no 2, 730-748 p.Article in journal (Refereed) Published
This contribution describes the synthesis, characterisation and evaluation of a novel biochip technology for the detection of the explosive substance 2,4,6-trinitrotoluene (TNT). Two types of thiols are self-assembled to produce the biochip on gold, namely oligo(ethylene glycol) (OEG)-alkyl thiols terminated with a hydroxyl group and a TNT-analogue (2,4-dinitrobenzene), respectively. Three different TNT-analogues are mixed in various proportions with hydroxyl-terminated OEG-thiols to obtain highly selective and sensitive biochips with a low non-specific binding. The produced self-assembled monolayers (SAMs) are thoroughly characterised with null ellipsometry, contact angle goniometry, infrared reflection absorption spectroscopy (IRAS) and X-ray photoelectron spectroscopy (XPS) and they all meet high standards in terms of molecular conformation, packing and orientation. The biochip is designed to function as a platform for a competitive label-free immunoassay and two real-time transducers – surface plasmon resonance (SPR) and quartz crystal microbalance (QCM) – are used to monitor the dissociation of on-line immobilised monoclonal antibodies produced against TNT. The three TNT-analogues are all potential candidates for the development of a functional biochip, though one of them displayed superior properties in terms of shorter recovery/stabilisation time after antibody immobilisation and a better response/loading capacity ratio. This is particularly evident when using low antigen (TNT-analogue) content in the mixed SAM.
Place, publisher, year, edition, pages
2006. Vol. 113, no 2, 730-748 p.
Explosives; Competitive immunoassay; Self-assembled monolayers; Quartz crystal microbalance; Surface plasmon resonance
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-14605DOI: 10.1016/j.snb.2005.07.025OAI: oai:DiVA.org:liu-14605DiVA: diva2:23999