Résumé
OBJECTIVE: To compare different pretreatment methods for determination of 10 metallic elements including Pb, Cd, As etc in Ganoderma extract. METHODS: Microwave digestion, automatic wet digestion and electrical heating wet digestion methods were used to conduct pretreatment of Ganoderma extact, then the contents of Pb, Cd, Hg, As, Cu, Fe, Mn, Zn, Al, Zn and Cr were determined by inductively coupled plasma mass spectrometry (ICP-MS). RESULTS: The contents of metallic elements determined by the three kinds of digestion methods were not statistically different except for Hg (P>0.05). The average recoveries of Hg in the Ganoderma samples were 65.28% and 70.39% when processed by automatic digestion and electrical heating digestion method, respectively, much lower than the value of microwave digestion method (98.31%). The recoveries of other metallic elements ranged from 92.19% to 103. 26% by the three kinds digestion methods, with RSDs less than 5%. CONCLUSION: Automatic digestion and electrical heating digestion methods are unable to meet the requirement for simultaneous determination of the 10 kinds of metallic elements in Ganoderma extract, however, microwave digestion method can. As the microwave digestion method is simple and rapid, so it is more suitable for the determination of heavy metals in Ganoderma. It is suggested to choose appropriate sample digestion method according to specific determination requirement on metallic elements in actual situation.