微波消解－溶出伏安法对食品中铜、铅、镉的同时测定

A method for the determination of Cd, Pb, Cu in food by mircrowave digestion (MWD) method as pretreatment procedures combined with anodic stripping voltammetry (ASV) using a rotating glassy carbon/mercury film electrode was proposed. A series of experimental conditions, such as the pressure and temperature of microwave digestion, pH of the buffer solution and deposition potential, were optimized. Under the optimal conditions, the linear ranges of Cu, Pb and Cd were 0.040-1.768, 0.080-1.768 and 0.040-1.768mg/L, respectively. The limits of detection (LODs) of Cu, Ph and Cd were 0.9984, 0.9982 and 0.9970, respectively and RSD of repeatabilities were 4.1%, 0.92%, 2.0%, respectively. The spiked recoveries of Cu, Ph and Cd were in the range of 98%-109%, 94%-103%, 100%-112%, respectively. The method showed good sensitivity and repeatibility, and was applied in the determination of Cu, Pb and Cd in real sample. The results were in good agreement with those obtained from the atomic emission spectrometry (AAS) method.