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Updated: Jul 11, 2026

ELIME (Enzyme Linked Immuno Magnetic Electrochemical) Method for Mycotoxin Detection
Published on: October 23, 2009
Highly sensitive detection of organophosphorus insecticides using magnetic microbeads and genetically engineered
Georges Istamboulie1, Silvana Andreescu, Jean-Louis Marty
1Université de Perpignan Via Domitia, Centre de Phytopharmacie, BIOMEM, 52 Av. Paul Alduy, 66860 Perpignan Cedex, France.
Abstract:
This work presents a biosensor for organophosphorus pesticides based on immobilisation of a highly sensitive genetically engineered acetylcholinesterase (B394) by affinity interactions on metal chelate-functionalised magnetic microbeads. The developed sensor has been compared with those based on the widely used Electric eel cholinesterase and a classical entrapment procedure in a polyvinylalcohol-based matrix. The use of the B394 enzyme allowed lowering both IC50 and LOD by a factor of 100 when compared with Electric eel enzyme sensor. The oriented and site-specific immobilisation combined with the high specificity of the B349 mutant allows a more sensitive detection of insecticides, concentrations as low as 1.31(-11)M (IC10) being detected for both pesticides chlorpyriphos-oxon and chlorfenvinphos.
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