基质匹配曲线校正-电感耦合等离子体质谱法测定血铅

Determination of lead in blood by matrix-matched calibration curve correction-inductively coupled plasma mass spectrometry

目的 建立基质匹配曲线校正-电感耦合等离子体质谱法(ICP-MS)测定血铅。方法 全血样品和空白全血分别采用0.5%硝酸-0.01%TritonX-100溶液直接稀释10倍得全血样品溶液和基质匹配溶剂。采用ICP-MS仪He模式,在线加入~(175)Lu为内标,以基质匹配溶剂校正标准工作曲线,根据标准工作曲线计算全血样品中铅的质量浓度。采用加标回收试验检测全血盲样,计算相对标准偏差和平均加标回收率;采用本方法与国家标准推荐方法分别检测3种牛血铅标准物质,评估本方法的准确度和精密度。结果 血铅在0.5~100.0μg/L范围内线性关系良好,相关系数为1.000,方法检出限为0.4μg/L,定量限为1.3μg/L。相对标准偏差分别为0.65%和1.10%,平均加标回收率为96.89%~99.73%,且3种牛血铅标准物质测定结果均在证书标准范围内。结论 基质匹配曲线校正-电感耦合等离子体质谱法线适用于血铅的高通量测定。

Objective To develop the matrix-matched calibration curve correction-inductively coupled plasma mass spec⁃trometry(ICP-MS)for the determination of lead in blood.Methods Whole blood samples and blank whole blood were pretreated by direct dilution with a solution of 0.5%nitric acid and 0.01%TritonX-100 to obtain whole blood sample solutions and matrix-matched solvents at a 10-fold dilution.The mass concentration of lead was determined by using an ICP-MS instrument in He mode.175Lu was added online as an internal standard.The standard working curve was calibrated with the matrix-matched solvent,and the mass concentration of lead in the whole blood samples was calculat⁃ed based on the standard working curve.Recovery tests were performed on whole blood blind samples by spiking,and the relative standard deviation and average recovery rate were calculated.The accuracy and precision of this method were assessed by comparing it with the method recommended in the national standard in detection of lead in three types of bovine blood lead standard materials.Results Good linearity was shown for lead at 0.5 to 100.0μg/L,with a correlation coefficient of 1.000.The detection limit of lead was 0.4μg/L,and the quantitation limit was 1.3μg/L.The relative standard deviations were 0.65%and 1.10%.The average recovery ranged from 96.89%to 99.73%.The lead de⁃termination results were all within the normal reference ranges specified by the three certified reference materials for bo⁃vine blood samples.Conclusion The matrix-matched calibration curve correction-ICP-MS is suitable for high-through⁃put determination of blood lead.