液相色谱-串联质谱法测定尿液中的可替宁

为了准确测定吸烟者与非吸烟者尿液中可替宁含量水平，建立了液相色谱-串联质谱（LC-MS/MS）测定方法。尿液经稀释、离心和过滤，引入LC-MS/MS，经Agilent Zorbax Eclipse XDB-C₁₈色谱柱（150 mm×2.1 mm，3.5 μm）分离，以0.1% 甲酸水溶液0.1% 乙酸甲醇溶液为流动相，采用梯度洗脱方式，以电喷雾离子源正离子多反应监测模式进行分析。方法检出限为0.08 μg/L，线性范围为1~500 μg/L，空白样品中加标回收率范围在94.3%~99.9%，精密度（以相对标准偏差计）为0%~3.2%。利用此方法检测了58个非吸烟者和246个吸烟者尿液中可替宁的含量水平，结果表明：吸烟者24 h尿液中的可替宁含量是非吸烟者的180多倍，但是由于个体之间以及吸烟行为之间的差异，尿液中的可替宁含量并不随卷烟主流烟气中烟碱含量的升高而升高。

Determination of Cotinine in Urine Using High Performance Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry

A high performance liquid chromatography-electrospray ionization tandem mass spectrometry(LC-ESI-MS/MS)method was developed for the determination of cotinine in urine.After dilution,centrifugation and filtration,the urine was injected to the LC-MS/MS.The analysis was performed on a Agilent Zorbax Eclipse XDB-C18 column(150 mm×2.1 mm,3.5 μm) using a gradient elution with the mobile phases of 0.1% formic acid buffer and 0.1% acetate in methanol(V/V),and determined by tandem mass spectrometry in positive ESI mode under multiple reaction monitoring mode.The limits of determination(S/N=3) was 0.08 μg/L,with a linear calibration range spanning 1—500 μg/L.The recoveris ranged from 94.3% to 99.9% at three spiked levels,the relative standard deviations(RSDs) ranged from 0 to 3.2%.The method was applied to detect the concertration of urine cotinine from 58 non-smokers and 246 smokers.Twenty-four hours urine cotinine levels in smokers was much more than 180 times that in non-smokers.However,due to the differences between individuals and smoking behavior,the concertration of urine cotinine did not increase with cigarettes nicotine in the mainstream smoke.