PREPARATION OF POLY(PYROMELLITIC DIANHYDRIDE-COTHIONIN) MODIFIED VOLTAMMETRIC SENSOR FOR THE DETERMINATION OF EPICATECHIN

Abstract

In this study, the electrochemical oxidation of epicatechin and its voltammetric sensing isshown at a sensitive platinum electrode modified with poly(pyromellitic dianhydride-co-thionin). Theelectrochemical response of the sensor was improved in the presence of both electro-inactive (sucrose,fructose, lactose) and electroactive (gallic acid, cafeic acid, ascorbic acid) interferants and displayed anexcellent analytical performance for the determination of epicatechin. A linear response was obtainedover a range of epicatechin concentrations from 0.05 mM to 0.30 mM and was shown to be useful forquantifying low levels of epicatechin in phosphate buffer solution, PBS, pH 7.00. Regression coefficient(R2) was found to be to be 0.9969. Limit of detection (LOD) was calculated as 1.8 × 10-5 M by using3s/m. Where m is the slope of the calibration curve and s is the standard deviation of the calibrationgraph calculated using the Excel Steyx function.