hide
Free keywords:
CARBAMATE PESTICIDES; ORGANOPHOSPHATE PESTICIDES; ENZYME-INHIBITION;
LIQUID-CHROMATOGRAPHY; GAS-CHROMATOGRAPHY; SAMPLESenzymes; biosensors; amperometric detection; pesticides; thin-layer
enzyme cell;
Abstract:
An amperometric biosensor for the detection of organophosphorus and carbamate type pesticides was developed. Acetylcholinesterase enzyme (electric eel) was immobilized in a thin-layer enzyme cell, and acetylthiocholine chloride (AcTCh) was used as substrate. Amperometric detection with glassy carbon electrode was performed in a stopped-flow FIA system. The inhibition effect of dichlorvos (DDVP), carbofuran, methomyl, and pirimicarb were examined: the linear measuring ranges were 0.001-0.1 mu mol l(-1), 0.001-0.1 mu mol l(-1), 0.2-1 mu mol l(-1), and 0.1-10 mu mol l(-1), respectively. Soil extract and apple juice were measured with spiking method. It was concluded that the biosensor can be used for screening pesticide residues in food and environmental samples.