Determination of carbamate pesticides by a cholinesterase-based flow injection biosensor

• Published in: International journal of food science & technology Vol. 36; no. 3; pp. 263 - 269
• Main Authors: Lee, Hye-Sung, Kim, Young-Ah, Chung, Duck Hwa, Lee, Yong Tae
• Format: Journal Article
• Language: English
• Published: Oxford UK Blackwell Science Ltd 01.03.2001; Blackwell Science
• Subjects: Acetylcholinesterase; Biological and medical sciences; carbaryl; carbofuran; Food industries; Food toxicology; Fundamental and applied biological sciences. Psychology; General aspects; inhibition; Medical sciences; Methods of analysis, processing and quality control, regulation, standards; Pesticides, fertilizers and other agrochemicals toxicology; sensor; Toxicology; Trace analysis; Agricultural chemical product; Carbofuran; Insecticide; Enzyme; Pesticides; Enzyme inhibitor; Esterases; Foodstuff; Acetylcholinesterase; Carbaryl(pesticide); Carboxylic ester hydrolases; Antimetabolic; Residue; Biosensor; Detection limit; Hydrolases; Carbamate; Chemical contamination; Flow injection
• ISSN: 0950-5423; 1365-2621
• DOI: 10.1046/j.1365-2621.2001.00453.x

A potentiometric flow injection‐type biosensor developed in our laboratory was used for the determination of carbamate pesticides. The principle of the biosensor is based on the inhibition of enzyme by pesticides, which is dependent on the concentration of the pesticides present. The sensor system consisted of a reactor with acetylcholinesterase immobilized on controlled pore glass and a detector with tubular H+‐selective membrane electrode. The sensor protocol established was applied to the analysis of nine carbamate pesticides. All the pesticides at 10−6 M inhibited the sensor enzyme, demonstrating the utility of the developed method. Treatment of the inhibited enzyme with pyridine‐2‐aldoxime restored nearly all of the enzyme activity allowing repeated use of the sensor. Calibration curves for carbaryl and carbofuran over the concentration range 10−11–10−4 M were obtained. The lower detection limits were 10−10 M and 10−11 M, respectively.