李阳　韩桂琪　何难　黄彪　彭成　国锦琳

摘要[目的]建立准确测定川芎中镉含量的分析方法。[方法]微波消解法消化经粉碎混匀的川芎块根样品0.1 g，消解总时间25 min，消化液赶酸后稀释定容100 mL，以石墨炉原子吸收法测定总镉浓度。选择1.0 g/L磷酸作基体改进剂提高灰化温度至550 ℃。[结果]方法检出限为0.08 mg/kg，线性范围为0.08～2.00 μg/L，日内精密度的RSD为0.2%～6.5%。测定5个种植区域的川芎样品共48份的加标样品回收率为96.0%～109.6%。[结论]该方法测定川芎中镉含量灵敏、准确、高效、易普及，为准确掌握川芎镉含量分布提供了可靠的定量方法。

关键词 镉含量；川芎；微波消解；石墨炉原子吸收法；定量测定

中图分类号 S567 文献标识码 A 文章编号 0517-6611（2016）05-130-03

Abstract[Objective]To establish an analysis method to accurately determine the cadmium concentration of Chuanxiong Rhizoma.[Method]The tuberous root of Chuanxiong Rhizoma was pulverized and 0.1 g of the powder was digested by microwave. After 25 min of digestion， the acid was drove by heating and diluted to 100 mL. The cadmium concentration of the sample solution was detected by graphite furnace atomic absorption. 1.0 g/L phosphoric acid was used as the matrix modifier and the ashing temperature was raised to 550 ℃.[Result]The detection limit was 0.08 mg/kg； linear range was 0.08-2.0 μg/L； RSD of intraday precision was 0.2%-6.5%. The recovery rates of 48 samples were 96.0%-109.6% in five planting areas.[Conclusion]This method is sensitive， effective and accurate to detect the cadmium concentration in Chuanxiong Rhizoma， and provides reliable quantitative method for the investigation of accurate distribution of cadmium concentration in Chuanxiong Rhizoma.

Key words Cadmium concentration； Chuangxiong Rhizoma； Microwave digestion； Graphite furnace absorption； Quantitative analysis

川芎是伞形科川芎Ligusticum chuanxiong Hort.的干燥根茎[1]，是重要川产道地药材，主产区成都的产量占全国总产量的90%以上，是我国中药出口创汇的重要品种。重金属超标问题是川芎国际贸易壁垒的主要成因，其中镉超标是川芎重金属超标问题中最突出的[2-4]。川芎中镉限量《中国药典》规定为0.3 mg/kg[1]，欧洲规定更为严格，为0.2 mg/kg[5]。

测定川芎中镉含量方法主要有湿消化-火焰原子吸收法[4，6]、湿消化-石墨炉原子吸收法[3]、湿消化-ICP/MS法[2]。火焰原子吸收灵敏度有限，湿消化-火焰原子吸收法取样量一般为1.0 g以上，样品前处理难度大、时间长，易造成损失，影响定量准确性；ICP/MS方法成本较高，尚不易普及；石墨炉原子吸收法灵敏度高，是测定川芎中微量镉的理想方法，但镉受热易挥发，湿消化敞口进行有可能损失且效率低，不适宜用于测定川芎中镉含量的样品前处理。……