Abstract: Objective To establish an online solid phase extraction-ultra high performance liquid chromatography tandem mass spectrometry （SPE-UPLC-MS/MS） method for the simultaneous determination of ketamine, norketamine and the precursor of hydroxyimine in water samples. Methods Pretreated by an online SPE column （2.1 mm×30 mm, 20 μm, Waters Oasis HLB）, samples were separated on a Waters ACQUITY UPLC HSS T₃ column （2.1 mm×100 mm, 1.8 μm） using gradient elution. The mobile phase consisted of acetonitrile and 0.1 % （volume fraction） formic acid aqueous solution. The multiple reaction monitoring （MRM） mode was used for MS analysis. Results Under the current conditions, the method was fully validated. It showed good specificity, accuracy and repeatability. The linear ranges of ketamine, norketamine and hydroxylimine were all 0.2-200 ng/L, and the limit of detection （LOD） for these analytes were 0.05 ng/L, 0.05 ng/L and 0.02 ng/L, respectively. The correlation coefficients were all more than 0.999. Conclusion Using the established method, the complete process of online extraction, separation and analysis of sewage samples can be finished in 13 minutes. The method has been applied to the monitoring of ketamine, norketamine and hydroxyimine in urban sewage samples successfully.

Key words: online solid phase extraction, UPLC-MS/MS, drug precursor, ketamine, norketamine, hydroxyimine

摘要： 目的 建立一种在线固相萃取-超高效液相色谱-串联质谱法（SPE-UPLC-MS/MS）同时测定水体中氯胺酮、去甲氯胺酮和易制毒前体羟亚胺。方法 采用多反应监测（MRM）模式，用Waters Oasis HLB柱（2.1 mm×30 mm，20 μm）进行固相萃取，采用Waters ACQUITY UPLC HSS T₃柱（2.1 mm×100 mm，1.8 μm）为固定相，柱温 40 ℃，以乙腈-0.1 %（体积分数）甲酸水溶液为流动相，按梯度洗脱程序进行分离。结果 通过系统的方法学验证，氯胺酮、去甲氯胺酮和羟亚胺的线性范围均为0.2~200 ng/L，相关系数均大于0.999，检出限分别为0.05、0.05、0.02 ng/L，具有较好的专属性、准确性和重复性。结论 基于SPE-UPLC-MS/MS建立了同时测定水体中痕量氯胺酮、去甲氯胺酮和羟亚胺分析的新方法，在13 min内实现了氯胺酮、去甲氯胺酮和羟亚胺的在线萃取、分离和分析全过程，并成功应用于城市污水监测。

关键词: 在线固相萃取, 超高效液相色谱-串联质谱法, 易制毒前体, 氯胺酮, 去甲氯胺酮, 羟亚胺