Determination of Stability Constants for Complexes of Ni(II) with Adenine and Guanine from Catalytic Linear Scan Voltammetric Currents

Abstract

The catalytic effects of adenine and guanine on the reduction of Ni(II) at the hanging mercury drop electrode were used to study the formation of complexes in the bulk of aqueous solutions at 25 °C and ionic strength 0.2 M. Complexation data were obtained from an analysis of the kinetic (catalytic) pure limiting currents, according to a method proposed previously. Values of 3.70 and 3.17 were determined for the logarithms of the stability constants corresponding to the formation of 1 : 1 complexes between Ni(II) – aquo ion and the neutral form of adenine and guanine, respectively.