自动石墨消解–电感耦合等离子体质谱法同时测定左氧氟沙星胶囊中7种金属元素

Simultaneous determination of 7 metal elements in levofloxacin capsules by automatic graphite digestion–inductively coupled plasma mass spectrometry

建立自动石墨消解-电感耦合等离子体质谱法(ICP-MS)同时测定左氧氟沙星胶囊中铅、铬、砷、镉、锡、铝、铁7种金属元素含量的方法。以HNO3-H2O2()体积比为1∶1为消解体系,采用自动石墨消解法消解左氧氟沙星胶囊样品,消解液除酸后,用5%硝酸溶液定容至50 mL,采用电感耦合等离子体质谱法对消解液进行测定,以内标法定量。铅、铬、砷、镉、锡、铝、铁的质量浓度在0.05~20.0μg/mL范围内与质谱响应值成良好的线性关系,相关系数均大于0.998,方法检出限为0.119~1.323μg/kg。样品加标回收率为91.2%~105.5%,测定结果的相对标准偏差为1.67%~3.46%(n=6)。该方法样品前处理简单,检出限低,测定结果准确,适用于左氧氟沙星胶囊等沙星类抗生素中多种金属元素残留的测定。

The method for simultaneous determination of lead,chromium,arsenic,cadmium,tin,aluminum and iron metal elements residues in levofloxacin capsule by automatic graphite digestion-inductively coupled plasma mass spectrometry(ICP-MS)was established.The sample of levofloxacin capsule was digested by automatic graphite digestion method with HNO3-H2O2(volume ratio 1∶1)as digestion acid system.After deacidification of digestion solution,samples were fixed volume to 50 mL with 5%nitric acid solution.The digestion solution was determined by inductively coupled plasma mass spectrometry,and quantify by internal standard method.The mass concentration of lead,chromium,arsenic,cadmium,tin,aluminum and iron had good linear relationship with the response value of mass spectrometry in the range of 0.05-20.0μg/mL,the correlation coefficients were all more than 0.998,and the detection limits were 0.119-1.323μg/kg.The recoveries of samples standard addition were 91.2%-105.5%,and the relative standard deviations of determination results were 1.67%-3.46%(n=6).The method is simple in pretreatment,low in detection limit and accurate in detection result,which is suitable for the determination of multiple metal elements residuals in floxacin antibiotics such as levofloxacin capsules.