Analytical Sciences

Abstract − Analytical Sciences, 19(2), 255 (2003).

Determination of Lead, Cadmium and Mercury in Microwavedigested Foodstuffs by RP-HPLC with an On-line Enrichment Technique
Zhangjie HUANG, Guangyu YANG,  Qiufen HU, and Jiayuan YIN
Department of Chemistry, Yunnan University, Kunming 650091, P. R. China
A new method for the simultaneous determination of lead, cadmium and mercury ions in microwave-digested foodstuffs by reversed-phase high-performance liquid chromatography combined with on-line enrichment technique has been developed. The foodstuff samples were digested by microwave digestion. The lead, cadmium and mercury ions can be precolumn derivatized with 5,10,15,20-tetrakis(3-aminophenyl)porphine (T3APP) to form color chelates; then, the Hg-T3APP, Cd-T3APP and Pb-T3APP chelates can be enriched and separated on a valve switching HPLC system combined with on-line enrichment technique. The linearity ranges are 0.01 - 120 ug/l for each metal ion. The detection limits (S/N = 3) of lead, cadmium and mercury are 1.2 ng/l, 0.5 ng/l and 0.8 ng/l, respectively. This method was applied to the determination of lead, cadmium and mercury in foodstuffs with good results.