Sequential voltammetric determination of chromium, thallium, cadmium, lead, copper and antimony in saline hemodialysis concentrates using electrolyte pH gradient

摘要

The sequential voltammetric determination of chromium, thallium, cadmium, lead, copper and antimony in dialysate concentrates (DCs), is presented herein. Chromium was quantified by adsorptive cathodic stripping voltammetry and thallium, cadmium, lead, copper and antimony were assayed by anodic stripping voltammetry. The novel method developed to test these samples exploits the effect of electrolyte pH gradient on voltammetric response. The limits of detection (LOD) ranged from 0.03 μg L-1 for cadmium to 0.27 μg L-1 for copper. Recoveries from spiked samples were 92.0-117.5%. This method was applied to the analysis of commercial DCs, where the investigated metals were found in some samples at concentrations between 0.16 μg L-1 for antimony and 140.00 μg L-1 for copper. Interferences and the reference method are discussed