优化基体改进剂后采用石墨炉原子吸收法对中药材中铅残留量检测方法的研究

目的:优化基体改进剂,建立石墨炉原子吸收法测定中药材中铅残留量的方法。方法:对基体改进剂的配比和用量进行了考察,并对灰化温度和原子化温度进行了优化,最终以2%磷酸二氢铵和1%硝酸镁各3μl作为基体改进剂,采用石墨炉原子吸收法对23种中药材中铅的残留量进行了研究。结果:方法检出限为0.085 mg/kg;在浓度为0μg/L～100μg/L时,线性关系良好,相关系数r=0.9998;相对标准偏差RSD为6.5%～9.5%;回收率在80.5%～109.1%之间。结论:通过优化基体改进剂,有效消除了基体的干扰,提高了方法的检测灵敏度。该方法具有快速、灵敏、准确等优点,适用于中药材中铅残留量的分析检测。

Study on the determination of lead residues in Chinese medicinal materials by graphite furnace atomic absorption spectrometry after optimizing the matrix modifiers

Objective:To develop a method of graphite furnace atomic absorption spectrometry to determine lead residues in Chinese medicinal materials by optimizing the matrix modifiers.Methods: By comparing different proportion and dosage between two matrix modifiers,and optimizing the ashing temperature and the atomization temperature,lead residues in 23 kinds of Chinese medicinal materials were determined by graphite furnace atomic absorption spectrometry,using 2% NH4H2PO4 3 μl and 1% MgNO3 3 μl as the matrix modifier.Results: The method detection limit was 0.085 mg/kg.Lead showed a good linear relationship in the range of 0 μg/L～100 μg/L,with the correlation coefficient of 0.9998.The relative standard deviation was 6.5%～9.5%.The recoveries were in the range of 80.5%～109.1%.Conclusion: By optimizing matrix modifiers,the interference from matrix effect was efficiently eliminated,and the sensitivity was improved.The method is suitable for the determination of the levels of lead in Chinese medicinal materials with satisfactory sensitivity,accuracy and precision.