超高效液相色谱串联质谱法检测血液中的氨曲南及甲硝唑

 目的 建立同时检测血液中氨曲南及甲硝唑的超高效液相色谱串联质谱分析方法。方法 以头孢拉定和氯霉素为内标，血液样品经乙腈沉淀蛋白后通过高效液相色谱分离，电喷雾离子源进行离子化，采用多反应监测方式(multiple reaction monitoring mode，MRM)对各化合物进行监测。结果 所建立的方法可同时检测血液中的氨曲南和甲硝唑成分，氨曲南在10～5 000 ng/mL、甲硝唑在1～1 000 ng/mL的线性范围内具有良好的线性关系，线性相关系数r均大于0.995；血液中氨曲南和甲硝唑的检出限分别为5和0.5 ng/mL (S/N=3∶1)；定量限分别为10和1 ng/mL (S/N=10∶1)；方法的日间及日内精密度均小于10%，准确度为 89.6%～97.5%。将此方法应用于1例医疗纠纷案件的鉴定，在涉案死者的血液中同时检出氨曲南及甲硝唑成分，血液中氨曲南及甲硝唑的质量浓度分别为438 ng/mL和15 μg/mL。结论 本研究所建立的分析方法灵敏度高、简便快速、专属性强、可靠性高，为司法鉴定实践中涉及氨曲南和甲硝唑的案件提供了技术支持和基础数据。

Analysis of aztreonam and metronidazole in blood by ultra performance liquid chromatography-tandem mass spectrometry

Objective To establish a UPLC-MS/MS method for the determination of aztreonam and metronidazole in blood. Methods Cefradine and chloramphenicol were used as the internal standard. Blood sample was made by protein precipitation with acetonitrile, and then was seprated by HPLC. Multiple reaction monitoring mode (MRM) for the parent ion and ion monitoring was used for each compound. Results The linearity of aztreonam in the range from 10 to 5 000 ng/mL and metronidazole in the range from 1 to 1 000 ng/mL were good (r>0.995). The quantification limit of the method for aztreonam and metronidazole were 5 and 0.5 ng/mL, respectively (S/N=3∶1). The inter-day and intra-day relative standard deviations (RSD) were less than 10%. The established method was used to detect aztreonam and metronidazole in a medical dispute case, the concentrations of aztreonam and metronidazole in the blood were 438 ng/mL and 15 μg/mL, respectively. Conclusions The method developed in the study is simple, sensitive and reproducible with its successful application into the qualitative and quantitative analysis of aztreonam and metronidazole.