固相萃取UPLC-MS/MS法同时检测水体中3种毒品代谢物

目的：建立固相萃取-超高效液相色谱-串联质谱法（SPE-UPLC-MS/MS）同时测定水体中甲基苯丙胺、氯胺酮和海洛因3种毒品代谢物，并用于检测水样中毒品代谢物的浓度。方法：水样过0.45 μm滤膜过滤，加入同位素内标，Oasis HLB固相萃取柱浓缩净化，然后溶于0.4 mL甲醇-水（1：9）中。采用UPLC BEH C₁₈（50 mm×2.1 mm，1.7 μm）色谱柱进行色谱分离，以0.01%甲酸-5 mmol·L^-1醋酸铵（A）-甲醇（B）为流动相，梯度洗脱，流速为0.3 mL·min^-1，柱温为40 ℃；采用ESI离子源正离子模式，多反应监测方式检测（MRM）。结果：甲基苯丙胺（METH）质量浓度在0.5~25 ng·mL^-1范围内呈良好的线性关系，氯胺酮（KET）和6-乙酰吗啡（6-MAM）质量浓度在0.5~10 ng·L^-1范围内呈良好的线性关系，相关系数均大于0.99；日内与日间精密度均小于9.7%；方法回收率均在94.0%~104.0%之间。检测水样中甲基苯丙胺检出率和检出浓度最高，城区毒品代谢物浓度较郊区高。结论：本方法经方法学验证，可同时对水体中甲基苯丙胺、氯胺酮和海洛因3种毒品代谢物进行检测，为评估毒品使用及药物滥用监测提供了分析手段。

Objective: To develop a solid-phase extraction combined with ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for determination of metabolites for methamphetamine,ketamine and heroin in wastewater,and to analyze the concentration of metabolites for three drugs in the wastewater.Methods: Wastewater was passed through a glass fiber filters (0.45 μm) to remove particulates.The filtered wastewater mixed with isotope internal standard and then loaded to Oasis HLB cartridges after these had been preconditioned sequentially with 6 mL methanol,6 mL ultrapure water and 6 mL ultrapure water at pH 2.The eluent was then evaporated to near-dryness using a rotational vacuum concentrator and reconstituted to a final volume of 0.4 mL in methanol with water mixed solution for analysis.UPLC-MS/MS was performed on a UPLC BEH C₁₈ (50 mm×2.1 mm,1.7 μm) column with the mobile phase consisting of 0.01% formic acid-5 mmol·L^-1 ammonium acetate (A) and methanol (B) in gradient elution.The flow rate was controlled at 0.3 mL·min^-1,and the column temperature was set at 40 ℃.A mass spectrometer equipped with electrospray ionization (ESI) source was used as a detector operated in the positive ion mode.Multiple reaction monitoring (MRM) mode was performed.Results: There were good linear relationship between peak areas and injection quality in the range of 0.5-10,0.5-25 and 0.5-25 ng·mL^-1 for methamphetamine,ketamine and 6-monoacetylmorphine with correlation coefficients all higher than 0.99,respectively.The overall relative recoveries ranged from 94.0%-104.0% with the intra-day and inter-day precision (RSD) were all below 9.7%.Both the highest frequency of detection and highest concentration of all wastewater samples corresponded to METH,the concentrations of metabolites of drugs in the urban were higher than in the suburban area.Conclusion: The established method is proved suitable for the simultaneous determination of methamphetamine,ketamine and heroin in wastewater,and is provides an analysis tool for the estimation of illicit drug use.