AChE biosensor based on zinc oxide sol–gel for the detection of pesticides

Zinc oxide has been used as a matrix for immobilization of acetylcholinesterase (AChE) and detection of the pesticide paraoxon. The immobilized enzyme retained its enzymatic activity up to three months when stored in phosphate buffered saline (pH 7.4) at 4 °C. An amperometric biosensor for the detection of paraoxon was designed. The biosensor detected paraoxon in the range 0.035–1.38 ppm and can be used to detect other AChE inhibiting organophosphate pesticides.