微波消解-电感耦合等离子体质谱法测定保健食品中铬、砷、镉、铅和汞

Determination of chromium,arsenic,cadmium,lead and mercury in health foods

目的建立微波消解-电感耦合等离子体质谱法测定保健食品中铬、砷、镉、铅和汞的含量。方法样品经硝酸-过氧化氢微波消解后，电感耦合等离子体质谱（ICP-MS）法测定保健食品中铬、砷、镉、汞、铅的含量。通过在线加入标准液校正，以^72Ge、^115In和^209Bi为内标。结果保健食品样品中各元素线性良好，相关系数为0．9994～1．0000；方法的检出限为铬0．010mg／kg、砷0．010mg／kg、镉0．003mg／kg、铅0．009mg／kg和汞0．001mg／kg；回收率为铬：92．3％～103．7％，砷98．7％～103．9％，镉95．6％～100．0％，铅99．8％～113．5％和汞88．9％～120．0％；相对标准偏差（RSD，n=6）为1．46～7．47％。结论实验结果表明该方法灵敏度高、稳定性好，可以满足保健食品中痕量铬、砷、镉、铅和汞的测定。

Objective A method was established for simultaneous determination of chromium, arsenic, cadmium, lead and mercury in health foods by inductively coupled plasma mass spectrometry （ ICP - MS）. Methods Samples were digested in nitric acid and hydrogen peroxide by microwave digestion. The operating conditions were optimized for the measurement of above 5 elements. ^72Ge, ^115 In and ^209 Bi were used as internal standard elements to compensate signal drift. Results The correlation coefficient of the five elements in health foods was above 0. 9994. The detection limits were in the range of 0. 001 mg/kg - 0.010 mg/kg, and the recoveries of the method were in the range of 88.9% - 120.0%. And the relative standard deviation （RSD, n = 6） of the method was less than 7.47%, Conclusion The method is suitable for the determination of trace Cr, As, Cd, Hg and Pb in health foods samples for its high sensitivity and good stability.