Citation:
Frank Davis, Karen A. Law, Nikos A. Chaniotakis, Didier Fournier, Tim Gibson, Paul Millner, Jean-Louis Marty, Michelle A. Sheehan, Vladimir I. Ogurtsov, Graham Johnson, John Griffiths, Anthony P.F. Turner, Seamus P.J. Higson, Chapter 15 Ultra-sensitive determination of pesticides via cholinesterase-based sensors for environmental analysis, In: S. Alegret and A. Merkoci, Editor(s), Comprehensive Analytical Chemistry, Elsevier, 2007, Volume 49, Electrochemical Sensor Analysis, Pages 311-330
Abstract:
This review is focussed towards the development of acetylcholinesterase enzymatic based biosensors for the quantification of trace concentrations of highly toxic pesticides via their inhibitory effect on the enzyme. Initial results were obtained using wild-type enzymes which have a broad spectrum of susceptibility to a variety of pesticides. The sensitivity and selectivity of the enzyme activity was improved by development and screening of a wide range of mutant enzymes. Optimal enzymes were then exploited within a range of sensor formats. A range of immobilisation techniques including adsorption based approaches, binding via proteins and entrapment within conducting polymers were all studied. The incorporation of stabilisers and co-factors were utilised to optimise electrode performance and stability - with both planar and microelectrode geometries being developed. Reproducible quantification of pesticides could be obtained at concentrations down to 10-17 M, representing a detection limit hitherto unavailable.
