同位素稀释超高效液相色谱-串联质谱法测定尿液中的可替宁

目的建立一种超高效液相色谱-串联质谱(UPLC-MS/MS)方法测定尿液中的可替宁,用于分析二手烟暴露儿童和成年吸烟者体内的尼古丁代谢情况。方法尿液样品加入可替宁d3同位素内标后用初始流动相稀释,涡旋混匀后过0.22μm滤膜进样分析。采用ACQUITY UPLC HSS T3色谱柱(2.1 mm×100 mm,1.8μm),流动相为0.01%甲酸的乙酸铵溶液(5 mmol/L)-乙腈,正离子扫描,多离子反应监测模式(MRM)检测,同位素内标法定量。结果方法的线性范围为0.1μg/L^150μg/L(r=0.9997),检出限为0.034μg/L(S/N=3)。样品加标回收率为97.0%~99.4%,相对标准偏差均<5.0%。利用该方法测定220份吸入二手烟的儿童和98份成年吸烟者尿液中可替宁的含量水平。结论本方法适用于尿液中可替宁的检测,具有操作简便、快速、灵敏、选择性好等特点。

Determination of cotinine in urine by ultra performance liquid chromatography-tandem mass spectrometry with isotope dilution

Objective To establish an ultra performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS)method to determine cotinine in urine and be to analyze nicotine metabolism in adult smokers and children who exposed to secondhand smoke by using this method.Methods Cotinine d3 isotope internal standard were added into the urine samples and diluted with initial mobile phase.After vortex mixing,the sample was filtrated with 0.22μm organic filter membranes before injection.Separation was performed on an ACQUITY UPLC HSS T3 column(2.1 mm×100 mm,1.8μm),in which 0.01%formic acid in 5 mmol/L ammonium acetate solution(V/V)and acetonitrile were used as the mobile phases.The condition of mass spectrometry was positive ESI mode under multiple-reaction monitoring mode(MRM)and the quantitative analysis was internal standard method.Results The linear range of the method for cotinine was within 0.1μg/L-150.0μg/L(r=0.9997),whereas detection limits was 0.034μg/L(S/N=3).The recoveries were within 97.0%-99.4%with the relative standard deviations less than 5.0%.This method was used to determine cotinine levels in the urine of 220 children exposed to secondhand smoke and 98 adult smokers.Conclusion The method could be applied to determine nicotine in urine effectively and quickly.