Simultaneous electrochemical determination of trace zinc(II), cadmium(II) and lead (II) in lipsticks using a novel electrode covered with bismuth/over-oxidized poly(xylenol blue) film

Abstract

The presence of zinc, cadmium and lead, which affects human health even at low concentrations, in different sample matrices is of great concern. This study proposes a dependable approach for the selective and sensitive identification of these cations with an over-oxidized poly(xylenol blue) film glassy carbon electrode coated with bismuth (Bi/PXBov.ox/GCE). Several techniques were used to chemically and physically evaluate the produced electrode surface. The following were chosen as the best conditions for determining these elements: 0.1 mol L-1 acetate buffer solution as supporting electrolyte (pH 4.5), −1.5 V accumulation potential, and 180 s accumulation duration. Under these conditions, the detection limits of Zn(II), Cd(II) and Pb(II) were found as 3.20 μg L-1, 0.21 μg L-1 and 1.98 μg L-1, respectively. Furthermore, this novel, cheap and easy-to-prepare Bi/PXBov.ox/GCE was also successfully used for the analysis of Zn(II), Cd(II) and Pb(II) in lipstick samples. The accuracy of the voltammetric measurements was assessed by comparing them to the data acquired with inductively coupled plasma mass spectrometry, and the results were found to be consistent.