电感耦合等离子体质谱法测定明目上清片中5种元素含量

Determination of Five Elements in Mingmu Shangqing Tablets by ICP-MS

目的建立测定明目上清片中5种元素含量的电感耦合等离子体质谱(ICP-MS)法。方法使用微波消解仪对样品进行预处理,等离子体射频功率为1550 W,采样深度为8.0 mm,等离子气体流速为15 L/min,雾化气流速为1.0 L/min,辅助气流速为0.9 L/min,蠕动泵转速为0.1 r/s。结果铅、镉、砷、汞、铜元素质量浓度分别在4~100 ng/m L、0.2~5 ng/m L、2~50 ng/m L、0.2~5 ng/m L、20~500 ng/m L范围内与仪器响应值线性关系良好(R^(2)>0.9995,n=6);精密度、重复性试验结果的RSD均小于4.0%;平均加样回收率分别91.97%,104.12%,107.05%,92.74%,103.46%,RSD均小于4.0%(n=6)。4家生产企业34批样品检出5种元素含量分别为0.21~2.64,0.03~0.16,0.20~12.14,0.00~1.14,2.33~6.21 mg/kg。按拟订的限度(分别为1.6,1.0,3.8,0.7,625 mg/kg),共有2批样品(涉及2家生产企业)存在超标现象,不合格率为5.88%。结论所建立的方法操作简单、快速、灵敏,结果准确,适用于明目上清片中5种元素的含量测定。

Objective To establish an inductively coupled plasma-mass spectrometry(ICP-MS)method for determining the contents of five elements in Mingmu Shangqing Tablets.Methods The samples were pretreated by a microwave digestion instrument.The plasma radio frequency power was 1550 W,the sampling depth was 8.0 mm,the plasma gas flow rate was 15 L/min,the atomization gas flow rate was 1.0 L/min,the auxiliary gas flow rate was 0.9 L/min,and the peristaltic pump speed was 0.1 r/s.Results The linear ranges of lead(Pb),cadmium(Cd),arsenic(As),mercury(Hg)and copper(Cu)were 4-100 ng/mL,0.2-5 ng/mL,2-50 ng/mL,0.2-5 ng/mL,20-500 ng/mL(R^(2)>0.9995,n=6)respectively.The RSDs of precision and repeatability tests were lower than 4.0%.The average recovery rates of the above five elements were 91.97%,104.12%,107.05%,92.74%,103.46%respectively,with RSDs lower than 4.0%(n=6).Pb,Cd,As,Hg and Cu were detected in 34 batches of samples from four manufacturing enterprises,with concentrations of 0.21-2.64,0.03-0.16,0.20-12.14,0.00-1.14,2.33-6.21 mg/kg respectively.According to the proposed limits(1.6,1.0,3.8,0.7,625 mg/kg),the element contents of two batches of samples(involving two manufacturing enterprises)were over the limit,with a disqualification rate of 5.88%.Conclusion The established method is simple,fast,sensitive and accurate,which is suitable for the determination of the five elements in Mingmu Shangqing Tablets.