Determination of lead and cadmium using a polycyclodextrin-modified carbon paste electrode with anodic stripping voltammetry

This work reports the use of alpha and beta-cyclodextrin-modified carbon paste electrodes (CPE(alpha-CD) and CPE(beta-CD)) to determine simultaneously Pb(II) and Cd(II) by means of the electrochemical technique known as anodic stripping voltammetry (ASV). Both modified electrodes displayed good resolution of the oxidation peaks of the said metals. Statistic analysis of the results strongly suggests that the CPE(beta-CD )exhibited a better analytical response that the CPE(alpha-CD), while the detection limits obtained for Pb(II) were 6.3 x 10(-7) M for the CPE(alpha-CD) and 7.14 x 10(-7) M for the CPE(beta-CD), whereas for Cd(II) they were 2.51 x 10(-6) M for the CPE(alpha-CD) and 2.03 x 10(-6) M for the CPE(beta-CD).