液相色谱-质谱法测定保健食品中的三价铬及六价铬含量

目的建立液相色谱-质谱法测定保健食品中总铬、三价铬及六价铬含量的分析方法,并与原子吸收法的检测结果进行比较。方法利用液相色谱-质谱法测定提取和氧化反应前后样品溶液中六价铬,分别计算总铬、三价铬和六价铬的量。结果 8批样品(3批胶囊,5批片剂)测定六价铬和总铬含量分别为188.7~257.8mg/kg和189.1~257.4 mg/kg。该方法可以实现保健食品中总铬、三价铬和六价铬的测定,六价铬的方法检出限为0.03 mg/kg,RSD=3.72%(n=5),定量限为1.0 mg/kg,RSD=3.07%(n=5)。结论该方法简便易行,与原子吸收法测定总铬的结果一致,可用于保健食品中铬及其形态的测定。

Determination of trivalent and hexavalent chromium in healthy food by liquid chromatography-mass spectrometry

Objective To establish the method for determination of total chromium, trivalent chromium and hexavalent chromium in healthy food by liquid chromatography-mass spectrometry (LC-MS), and compare the results with atomic absorption method. Methods The hexavalent chromium in sample solution before and after extraction and oxidation was determined by LC-MS, and the total chromium, trivalent chromium and hexavalent chromium were calculated, respectively. Results The content of total chromium and hexavalent chromium of 8 batches of samples (3 batches of capsule and 5 batches of tablet) were 188.7~257.8 mg/kg and 189.1~257.4 mg/kg, respectively. The limit of detection of hexavalent chromium was 0.03 mg/kg with RSD of 3.72% (n=5), and the limit of quantitation was 1.0 mg/kg with RSD of 3.07% (n=5). Conclusion The established method is simple and easy, and can be applied for determination of total chromium, trivalent chromium and hexavalent chromium in healthy food. The results of this method are consistent with those of atomic absorption method, which can be used for the determination of chromium and its forms in healthy food.