title: Highly sensitive detection of organophosphorus insecticides using magnetic microbeads and genetically engineered acetylcholinesterase.
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.
authors.affiliation: Université de Perpignan Via Domitia, Centre de Phytopharmacie, BIOMEM, 52 Av. Paul Alduy, 66860 Perpignan Cedex, France.
authors.forename: Georges
authors.initials: G
authors.lastname: Istamboulie
authors.forename: Silvana
authors.initials: S
authors.lastname: Andreescu
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Marty
authors.forename: Thierry
authors.initials: T
authors.lastname: Noguer
mesh_terms: D000110:Acetylcholinesterase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods; D005818:Genetic Engineering / Q000379:methods; D007306:Insecticides / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D008280:Magnetics; D008863:Microspheres; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000737:chemistry / Q000378:metabolism; D015203:Reproducibility of Results