Kinetic Evaluation of the Inhibition of Acetylcholinesterase for use as a biosensor

Abstract

The release of pesticides into the environment has increased , and there is a lack of monitoring of these contaminants. Since the conventional methods of monitoring these contaminants are compl icated , costly and time - consuming, mechanisms based on ace t ylcholinesterase inhibition have emerged as simple and rapid tools for such applications. However, the acetylcholinesterase ’s effectiveness as a sensing element in such biosensor systems depend­ s on the conditions selected to measure acetylcholinesterase activity and the concentration of substrate or inhibitor, which in turn affect the reaction rates. Therefore, i n the present work, the factors affecting the acetylcholinesterase activity were investigated and inhibition experiments were carried out to evaluate the kinetic parameters. The inhibition rate constant for acetylcholinesterase K i was found to be 1.9 ppm. The kinetic parameter K m was found to be 3.8mM and V max was found to be 1.3µM/min from the Eadie-Hofstee plot. The kinetic study using Lineweaver-Burk method showed mixed type of inhibition of acetylcholinesterase with carbofuran.