原子吸收光谱法考察不同提取方法对白芷中重金属溶出的差异

目的 利用原子吸收光谱法（atomic absorption spectrometry， AAS）研究白芷在不同提取工艺下所溶出的4种重金属（Cr、Cd、Pb和Cu）的差异。方法 采用水提法和醇提法提取白芷药材中各金属元素，分别用微孔滤膜和大孔树脂将各元素分离为可溶态与悬浮态、有机态与无机态，用湿法消解法提取金属元素，再利用AAS测定4种金属元素在原药材中的总质量比与各种形态中的质量比，并进行形态分析。结果 4种元素的提取率为25.14%~49.62%，加样回收率为96.09%~100.43%，RSD<3%（n=6）。传统水提法重金属的溶出率较低；Pb和Cu在醇提时的提取率明显较高；各元素在水煎液和醇煎液中，悬浮态含量均高于可溶态；各元素可溶态中，无机态含量均高于有机态；Cu的有机态含量在水煎时较醇煎时高（24.33% vs 13.57%）。结论 通过优化白芷药材的提取方法可以有效降低药材中重金属的溶出，从而达到减毒的目的。
Objective To apply atomic absorption spectrometry (AAS) for studying the differences in metal element dissolution (Cr, Cd, Pb and Cu) from Angelica dahurica following different extraction procedures. Methods The above four elements were extracted by water extraction and ethanol extraction methods. The water-soluble fraction and suspension fraction were separated from decocted solution by microporous filtering film; the water-soluble fraction was further divided into organic fraction and inorganic fraction by macroporous adsorption resin. The total contents of Cr, Cd, Pb and Cu and the amounts in different fractions were determined by wet digestion method and AAS, and morphological analysis was conducted. Results The extraction rates for the four elements were in the range of 25.14%-49.62%, with the sample recovery rates ranging 96.09%-100.43% and the relative standard deviation (RSD) being≤3% (n=6). Dissolution rate of metal elements by traditional water extraction method was low. The extraction rates of Pb and Cu by ethanol extraction method were higher than those of the water extraction method. Both in water decoction and ethanol decoction, the contents of four elements in the suspended species and inorganic species were higher than those in the soluble species and organic species. Cu content in organic species in water decoction was higher than that in ethanol decoction (24.33% vs 13.57%). Conclusion The metal element dissolution from Angelica dahurica can be decreased by optimizing the extraction method, which finally leads to reduced toxicity