Study of kinetic parameters and development of a voltammetric sensor for the determination of butylated hydroxyanisole (BHA) in oil samples

摘要

Electrochemical behavior of artificial antioxidant, butylated hydroxyanisole (BHA), was investigated at a glassy carbon electrode modified with poly L- cysteine [poly (L- Cys/GCE)]. BHA exhibits a pair of well - defined redox peak on L- cysteine modified GCE with Epa = 69 mV and Epc = 4 mV. The modified electrode showed good electrocatalytic activity towards the oxidation of BHA under optimal conditions and exhibited a linear response in the range from 1.0 × 10⁻⁵ to 1.0 × 10⁻⁶ M with a correlation coefficient of 0.998. The limit of detection was found to be 4.1 × 10⁻⁷ M. The kinetics parameters of the proposed sensor such as heterogeneous electron transfer rate, ks, and charge transfer coefficient,α, was calculated and found to be 1.20 s⁻¹ and 0.575 respectively. The average surface concentration of BHA on the surface of poly (L- Cys/GCE) was calculated to be 3.18 × 10⁻⁴ mol cm⁻². The analytical utility of the proposed sensor was evaluated by the successful determination of BHA in coconut oil and sesame oil samples.