尿液中尼古丁和可替宁QuEChERS预处理气相色谱测定法建立

Determination of nicotine and cotinine in urine with QuEChERS sample preparation-gas chromatography

目的建立同时检测尿液中尼古丁和可替宁的QuEChERS样品预处理-气相色谱法。方法于2015年11月22日—12月12日,采集重庆医科大学6例吸烟者和10例不吸烟者尿液样本,通过QuEChERS提取和净化后,经非极性的DB-5 ms毛细管色谱柱分离,氢火焰离子化检测器(FID)检测,保留时间定性,峰面积定量。结果尿液中尼古丁和可替宁的线性范围分别为0.5~500μg/mL(r=0.999 8)和5~500μg/mL(r=0.998 9),最低检出限(LOD)分别为0.09和0.75μg/mL。2种待测物日内的相对误差(RE)和变异系数(CV)<10.0%,日间RE和CV<10.4%。尼古丁和可替宁的加标回收率分别在93.2%~107.8%和94.6%~99.2%范围内。结论建立的方法操作简单、快速、成本低且有机试剂用量少,适于暴露者的烟草暴露剂量评估。

Objective To develop a QuEChERS-gas chromatography method for simultaneous determination of nicotine and cotinine in urine samples. Methods Urine samples were collected from 6 smokers and 10 non-smokers at Chongqing Medical University ; then the samples were extracted and purified with quick, easy, cheap, effective, rugged, and safe （QuEChERS） method and then separated via a non-polar DB-5 ms capillary chromatographic column and determined with flame ionization detector （FID）. Qualitative and quantitative analyses were performed using retention time and peak area. Results The linear ranges of nicotine and cotinine for the detected samples were 0. 5 - 500 μg/mL （ r = 0. 9998 ） and 5 - 500 μg/mL （ r = 0. 998 9 ）, with the limit of detection （LOD） of 0. 09 μg/mL and 0. 75 μg/mL, respectively. The intra-day and inter-day relative error （RE） and coefficient of variation （CV） of nicotine and cotinine detections were less than 10. 0% and 10. 4%. The mean recoveries of nicotine and cotinine were 93.2% - 107.8% and 94. 6% -99.2% ,respectively. Conclusion The method developed is simple, fast, cost-effective, and suitable for the assessment of tobacco exposure dose and the detection of metabolic dynamics of tobacco exposure.