Detection of Chlorpyrifos in Milk using an Amperometric Biosensor based on Acetylcholinesterase

Abstract

This work explores the use of an enzymatic amperometric biosensor, as an analysis method capable of determining the concentration of chlorpyrifos in raw cow's milk, compared in simultaneous runs with the results obtained with the gas chromatography technique. The enzyme acetylcholinesterase was used as a biological element, which was immobilized on electrodes of different material of the screen-printed type by the cross-linking method. The kinetic constants of the enzyme, free and immobilized, were determined. Validation of the technique for the quantification of chlorpyrifos by gas chromatography was performed, several optimization parameters were evaluated for the use of the biosensor and the validation of this as a tool to detect chlorpyrifos in milk was done. This paper concludes that the amperometric biosensor is a useful tool for the qualitative determination of chlorpyrifos in milk in real time.