Chemometric Analysis of Voltammetric Data on Metal Ion Binding by Selenocystine
journal contributionposted on 2012-06-28, 00:00 authored by Rui Gusmão, José Manuel Díaz-Cruz, Cristina Ariño, Miquel Esteban
The behavior of selenocystine (SeCyst) alone or in the presence of various metal ions (Bi3+, Cd2+, Co2+, Cu2+, Cr3+, Ni2+, Pb2+, and Zn2+) was studied using differential pulse voltammetry (DPV) over a wide pH range. Voltammetric data matrices were analyzed using chemometric tools recently developed for nonlinear data: pHfit and Gaussian Peak Adjustment (GPA). Under the experimental conditions tested, no evidence was found for the formation of metal complexes with Bi3+, Cu2+, Cr3+, and Pb2+. In contrast, SeCyst formed electroinactive complexes with Co2+ and Ni2+ and kinetically inert but electroactive complexes with Cd2+ and Zn2+. Titrations with Cd2+, Co2+, Ni2+, and Zn2+ produced data that were reasonably consistent with the formation of stable 1:1 M(SeCyst) complexes.