Simultaneous determination of electroactive and non-electroactive food preservatives by novel capillary electrophoresis with amperometric detection

A novel capillary electrophoresis and amperometric detection method was achieved by adding an electroactive additive (3,4-dihydroxybenzylamine, 3,4-DHBA) to the running buffer, so that both electroactive and non-electroactive food preservatives were simultaneously determined. Under the selected optimum conditions, four electroactive preservatives (methylparaben, ethylparaben, propylparaben and butylparaben) and two non-electroactive preservatives (potassium sorbate and sodium lactate) were well separated and sensitively detected with detection limits (S/N = 3) ranging from 1.06 × 10⁻⁸ to 2.73 × 10⁻⁶ g mL⁻¹. This method has been successfully employed for the determination of both electroactive and non-electroactive preservatives in several food commodities.