超级微波消解-电感耦合等离子体质谱法（ICP-MS）检测砂仁中的8种元素

Determination of Eight Elements in Amomum villosum by Super Microwave Digestion/Inductively Coupled Plasma Mass Spectrometry

摘要:

建立了超级微波消解-电感耦合等离子体质谱仪（ICP-MS）同时测定药食同源食品-砂仁中铝、铬、镍、砷、锡、镉、汞、铅8种元素的快速方法。HNO3-H2O作消解液，利用ICP-MS检测，在动能甄别模式下（KED），采用内标法，结果表明各元素检出限低，线性关系良好，相关系数（r）0.9997~1.0000（Hg为0.9935），检出限0.00025~0.25 μg/kg。用该方法对标准物质大米（GBW10010）、丹参GBW（E）090066进行方法验证，结果均在证书的范围以内；选取广东砂仁实验，加标回收率85.71%~109.09%，相对标准偏差1.93%~8.17%。通过对市场上销售的不同产地砂仁（广西、云南、海南、广东）进行检测分析，8种元素含量有差异，主要分布在果壳；壳中Al含量最高，范围为437.32~613.45 mg/kg，广西产地最高；壳中Pb含量范围为1.10~4.56 mg/kg，海南产地最高；壳、果仁的Ni含量分布相当，分别0.42~2.06 mg/kg、0.22~2.29 mg/kg；壳中Cr范围0.53~1.05 mg/kg；所有样品Cd<0.04 mg/kg；Hg、Sn只分布在壳中，Hg均为0.01 mg/kg、海南砂仁壳Sn、As最高分别是0.10 mg/kg、1.05 mg/kg。该方法精密度和准确度高，适合砂仁进行多元素分析，Cd、Hg、Sn、As均低于国家标准规定的限量，Pb、Ni、Al建议纳入风险监测指标。

Abstract:

A rapid super-microwave-digestion/ICP-MS method was established for the simultaneous determination of aluminum (Al), chromium (Cr), nickel (Ni), arsenic (As), tin (Sn), cadmium (Cd), mercury (Hg), and lead (Pb) in Amomum villosum, a plant with medicinal and nutritional value. A HNO3-H2O super microwave digestion system was employed to digest the Amomum villosum samples, and the contents of the aforementioned elements were determined by ICP-MS in kinetic energy discrimination (KED) mode. Moreover, the internal standard method was adopted to improve the matrix effect and interference. The detection limits of all the investigated elements were found to be low (0.00025~0.25 μg/kg). Adequate linear relationships between the signals and concentrations, and correlation coefficients (r) within 0.9997~1.0000 were obtained [r(Hg)=0.9935]. The proposed method was validated using standard reference materials, namely rice (GBW10010) and Salvia miltiorrhiza (GBW(E)090066), and the results were found to be within the recommended ranges of the references. The spiked recovery rates of Amomum villosum samples sourced from Guangdong were found to be 85.71%~109.09%, with relative standard deviations of 1.93%~8.01%. The analysis of Amomum villosum samples sourced from different locations (Guangxi, Yunnan, Hainan, and Guangdong) revealed variations in the contents of the target elements, with the differences being primarily reflected in the shell components. The Al content in the shells was found to be the highest (455.59~613.45 mg/kg), with the Guangxi-based samples exhibiting the highest Al content among the samples. The content of Pb in the shells was found to be in the 0.68~4.56 mg/kg range, with the samples sourced from Hainan exhibiting the highest Pb content. The Ni contents of the shells (0.42~2.06 mg/kg) and nuts (0.22~2.29 mg/kg) were found to be similar. The Cr content of the shell was estimated to be 0.53~1.05 mg/kg, and the Cd content was below 0.04 mg/kg. Hg and Sn were found to be present only in the shells. In particular, the content of Hg was ascertained to be 0.01 mg/kg in all the samples. The highest contents of Sn (0.10 mg/kg) and As (1.05 mg/kg) were detected in the shells of samples sourced from Hainan. The proposed method exhibits high precision and accuracy, and sufficient suitability for the determination of multiple elements in Amomum villosum. The contents of Cd, Hg, Sn, and As are all lower than the limits recommended by national standards. Additionally, the inclusion of Pb, Ni, and Al in risk monitoring indicators was recommended.