Alumina sol-gel/sonogel-carbon electrode based on acetylcholinesterase for detection of organophosphorus pesticides.
Two new amperometric biosensors based on immobilization of acetylcholinesterase on a sonogel-carbon electrode for detection of organophosphorous compounds are proposed. The electrodes were prepared applying high-energy ultrasounds directly to the precursors. The first biosensor was obtained by simple entrapping acetylcholinesterase in Al(2)O(3) sol-gel matrix on the sonogel-carbon. The second biosensor was produced in a sandwich configuration. Its preparation involved adsorption of the enzyme and modification via a polymeric membrane such as polyethylene glycol and the ion-exchanger Nafion. The optimal enzyme loading was found to be 0.7 mIU. Both biosensors showed optimal activity in 0.2 M phosphate buffer, pH 7.0, at an operating potential of 210 mV. The detection limit achieved for chlorpyriphos-ethyl-oxon was 2.5x10(-10)M at a 10-min incubation time.
Zejli
Hanane
H
Centre de phytopharmacie, Université de Perpignan-Biomem, Perpignan Cedex, France.
Hidalgo-Hidalgo de Cisneros
José Luis
JL
Naranjo-Rodriguez
Ignacio
I
Liu
Baohong
B
Temsamani
Khalid Riffi
KR
Marty
Jean-Louis
JL
D000110:Acetylcholinesterase / Q000378:metabolism*; D000537:Aluminum Oxide / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D004566:Electrodes; D006863:Hydrogen-Ion Concentration; D008855:Microscopy, Electron, Scanning; D009943:Organophosphorus Compounds / Q000032:analysis* / Q000737:chemistry; D010575:Pesticides / Q000032:analysis* / Q000737:chemistry*; D044367:Phase Transition; D015203:Reproducibility of Results
D009943:Organophosphorus Compounds; D010575:Pesticides; D002244:Carbon; D000110:Acetylcholinesterase; D000537:Aluminum Oxide