Determination of cadmium with a sequential injection lab-on-valve by anodic stripping voltammetry using a nafion coated bismuth film electrode

摘要

This work exploited a sequential injection lab-on-valve (LOV) system for the determination of cadmium by anodic stripping voltammetry (ASV). A miniaturized electrochemical flow cell (EFC) was fabricated in LOV, in which a nation coated bismuth film electrode was used as working electrode The cadmium was electrodeposited on the electrode surface in bismuth solution, and measured with the subsequential stripping scan. Under optimal conditions, the proposed system responded linearly to cadmium concentrations in a range 20-100.0 mu g L-1. The detection limit of this method was found to be 0 88 mu g L-1 By loading a sample volume of 800 mu L, a sampling frequency of 22 determinations h(-1) was achieved. The repeatability expressed as relative standard derivation (R.S.D.) was 3.65% for 20 mu g L-1 cadmium (n =11). The established method was applied to analysis of trace cadmium in environmental water samples and the spiked recoveries were satisfactory.