Study On The Method Of Assaying Inorganic Elements Of Chinese Medicinal Herb

In this study, 58 batches of Chinese medicinal herb were collected, which including 16 batches of Dangshen, 10 batches of Longdan, 22batcb.es Ezhu and 10 batches of Jiegeng. These four kinds of above-mentioned herbal medicine were the objects in this study, seven kinds of nutrition trace elements and five kinds of toxic heavy metal elements were analyzed. The method of assaying the inorganic elements in four kinds of Chinese medicinal herb was established.The establishment of solvent and condition in microwave digest method were studied. The optimal digest acid solvent was produced by Beijin No.2 Chemical Reagent Company .The optimal pressure and temperature of microwave digest were 1000-1400 kPa and 150-170℃, respectively.The samples were digested by closed-versel microwave. The solution was directly analyzed by ICP-MS. Select internal standard element Ge , In and Bi for the method by which the analyse signal drife is corrected by the signal of another element (internal standard elements) added to both the standard solution and sample. To establish an ICP-MS method for the determination of nutrition trace elements, including Fe, Mn, Cr, Zn, Ba, Co and Ni, in four kinds of Chinese medicinal herb. For all the analyzed elements, the linear ranges for nutrition trace elements were as follows: Cr : 0—40μg·L^-1, Fe : 0—10μg·mL^-1, Mn : 0-500μg·L^-1, Co : 0-10μg·L^-1, Ni : 0-40μg·L^-1, Zn : 0-200μg·L^-1, Ba : 0—10μg·mL^-1. The correlative coefficient of the calibration curves was over 0.9991 and its RSD was lower than 4.5 %. Standard reference material was the leaves of tea. The results showed that mensuration value was accord with standard reference material value. This method was convenient, quick-acquired, accurate and highly sensitive. This study can provide method for the content comparison of nutrition trace elements of Chinese medicinal herb from different habitats.To establish an ICP-MS method for the determination of toxic heavy metal elements, including Cu, Cd, Hg, Pb and As, in four kinds of chinese medicinal herb. The samples were digested by closed-versel microwave. The solution was dircctly analyzed by ICP-MS. Select internal standard element Ge, In, Bi and Au for the method by which the analyse signal drife is corrected by the signal of another element (internal standard elements) added to both the standard solution and sample. For all the analyzed elements, the linear ranges for toxic heavy metal elements were as follows: Cu: 0～100μg·L^-1, Cd: 0～10μg·mL^-1, Hg: 0～10μg·mL^-1, Pb: 0～20μg·mL^-1), As: 0～20μg·mL^-1. The correlative coefficient of the calibration curves was over 0.9992 and its RSD was lower than 7.7%. From the determination results of 58 batches of samples, we can conclude that the contents of toxic heavy metal elements in one specie herb medicine from different habitats are greatly different, which also reflects the big difference of soil, water quality and other environment factors in different regions. The contents of heavy metal elements in most of these samples are exceedingly over the standard. The related official section should pay highly attention to this phenomenon, and enhance the quality controlment of Chinese medicinal herb. This method was convenient, quick-acquired, accurate and highly sensitive. The study can provide the reference of limit of toxic heavy metal elements for Chinese medicinal herb.