X射线荧光光谱法快速测定防风中的金属元素含量

目的：采用X射线荧光光谱法（XRF）测定防风样品中Mg、Ti、V、Cr、Mn、Co、Ni、Cu、Zn、As、Ba、Pb和Bi等金属元素含量，实现大量中药材中多元素同时快速测定。方法：1）标样制备：ICP-AES测定多种样品中元素含量，选择其中元素含量较低的防风样品作为空白样品；在空白样品中精密加入计量的多元素标准溶液，冷冻干燥法制备中药模拟标样。2）样品检测：在XRF最佳测定条件下，以硼酸镶边压片，利用中药模拟标样建立标准曲线，并采用经验系数法进行基体校正；XRF测定不同产地的防风中金属元素含量。3）方法验证：XRF测定结果与ICP-AES结果进行t检验，评价2种方法测定结果是否存在显著性差异。结果：XRF的检出限在0.17~243 μg·g^-1之间；对同一批次防风样品，在相同的实验条件下重复测定7次，所有元素的相对标准偏差（RSD%）均小于4.0%；t检验结果表明XRF测定结果与ICP-AES测定结果均值无显著性差异。结论：XRF法无需对样品进行复杂的前处理，操作简单，测定迅速，结果准确，适用于中药中多元素同时快速测定。

Objective: To determine the content of Mg, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, As, Ba, Pb and Bi rapidly in Fangfeng, a kind of Traditional Chinese Medicine by X-ray fluorescence spectrometry(XRF)so as to establish an XRF method for the rapid determination of multi-element in large amount of Traditional Chinese Medicine. Method: The samples with low concentration of metal elements were selected as blank samples. Metric multi-element standard solution was added in the blank samples and freeze-dried to make TCM analog standard samples. The samples were edged with boric acid. Under the optimal conditions, the standard curves were established with TCM analog standard samples. Besides, the experience coefficient method(EC)was used for matrix adjustment. Finally, the new established standard curves were used to determine metal elements in Fangfeng from different origins. The data was compared with the results from ICP-AES by t test to assess whether there was significant difference between XRF and ICP-AES. Result: The detection limit of XRF was 0.17-243 μg·g^-1 and its RSD(n=7)was found to be less than 4.0%. The accuracy of XRF was not significantly different comparable to that of the ICP-AES by t test. Conclusion: Compared with other methods, XRF is simple, rapid, high efficient and is without preparation. So rapid content determination of metal elements in Traditional Chinese Medicine can be achieved by XRF.