Sensitive determination of bisphenol A in plastic products by derivative voltammetry using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan

摘要

A sensitive and reliable electrochemical method was developed for determination of bisphenol A (BPA) in plastic products using an acetylene black paste electrode coated with salicylaldehyde-modified chitosan (denoted as S-CHIT/ABPE). In the second-order derivative linear sweep voltammetry technique, BPA yielded a very sensitive and well-defined oxidation peak at 842 mV in 0.2 mol L~(-1) HC1 solution. Owing to its unique structure and extraordinary properties, S-CHIT/ ABPE showed higher accumulation efficiency toward BPA compared with bare ABPE, and significantly enhanced the oxidation peak current of BPA. Under the optimum conditions, the oxidation peak current was proportional to the concentration of BPA over the range of 4.0 × 10~(-8) mol L~(-1)～ 1.0 × 10~(-5)mol L~(-1). The detection limit (S/N = 3) was 2.0 × 10~(-8)mol L~(-1). The fabricated S-CHIT/ABPE not only exhibited strong adsorption capacity toward BPA, but also provided remarkable stable and quantitatively reproducible analytical performance. Additionally, this newly-developed method possesses some obvious advantages including high sensitivity, extreme simplicity, rapid response and low cost.