K. G. Reddy, G. Madhavi, B. Swamy
Apr 1, 2013
Citations
1
Influential Citations
23
Citations
Journal
Journal of Molecular Liquids
Abstract
Abstract Candida Rugosa Lipase mobilized sensor method was developed for the detection of organophosphorus pesticides like methyl parathion. Here p-Nitrophenyl Acetate was used as a substrate which releases p-Nitrophenol by the enzymatic hydrolysis and gives an anodic oxidation on electrochemical oxidation peak potential at 0.05 V versus SCE. Methyl parathion is a toxic substance and releases p-Nitrophenol when it is hydrolyzed and it also has the property of inhibiting the enzymatic activity and this is taken as a basis for the inhibition studies. The current response under the influence of pH, substrate concentration, enzyme concentration and time variation effects on the hydrolysis process was studied for the reaction between enzyme and substrate which releases p-Nitrophenol. A linear calibration for the methyl parathion was obtained in the concentration range of 10–70 ppb with a correlation coefficient of 0.948 under the optimized conditions by following the incubation time of 25 min. The detection limit was found as 26.32 ppb of methyl parathion with optimal conditions of 750 μΜ substrate concentration, 125 U of enzyme, pH 7.0, 25 min of hydrolysis time and incubation time of 25 min and the proposed method has a quantification limit of 87.72 ppb.