头发中尼古丁和可替宁的超高效液相色谱-串联质谱测定法

Determination of nicotine and cotinine in hair by ultra high performance liquid chromatographytandem mass spectrometry

目的建立头发中尼古丁和可替宁的超高效液相色谱串联质谱(UPLC-MS-MS)测定方法。方法头发样品用Na OH溶液完全消解后用二氯甲烷+甲醇(3+1)萃取,以10 mmol/L乙酸铵(含0.1%甲酸)-乙腈作为流动相进行梯度洗脱,超高效液相色谱串联质谱多反应监测(MRM)模式测定,内标法定量。结果尼古丁在2~200μg/L的范围内,所得回归方程为y=1.296 7x-2.379 9,r=0.999 6;可替宁在0.2~20μg/L的范围内,所得回归方程为y=1.099 2x-0.005 15,r=0.999 9。以3倍信噪比计算,当取样量为50 mg时,尼古丁和可替宁检出限分别为0.01μg/g和0.001μg/g。该方法所得尼古丁的平均回收率在75.0%~97.0%之间,可替宁的平均回收率在90.0%~102.0%之间,RSD<5%。结论本方法简便、快速、准确,适用于被动吸烟人群头发中尼古丁和可替宁含量的测定。

Objective To establish a method for the determination of nicotine and cotinine in hair by ultra high performance liquid chromatography-tandem mass spectrometry（UPLC-MS-MS）. Methods The hair samples were digested with Na OH solution and extracted with a mixed solvent dichloromethane-methanol（V∶V=3∶1）. The nicotine and cotinine were separated with acetonitrile and 10 mmol/L ammonium acetate（containing 0.1% formic acid,V∶V） aqueous solution as mobile phase for gradient elution,determined by UPLC-MS-MS in the multiple-reaction monitoring（MRM） mode and quantified by internal standard.Results In the range of 2-200 μg/L, the correlative regression equation of nicotine was y=1.296 7x-2.379 9,r=0.999 6;In the range of 0.2-20 μg/L,the correlative regression equation of cotinine was y =1.099 2x-0.005 15,r =0.999 9. The spiked recoveries were 75.0%-97.0% for nicotine（RSD〈5%） and 90.0%-102% for cotinine（RSD〈5%）. The limits of detection were 0.01μg/g for nicotine and 0.001 μg/g for cotinine invovled in the sample amount of 50 mg. Conclusion The method is simple,rapid,sensitive, accurate and applicable to the determination of nicotine and cotinine in hair of passive smoking people.