液液萃取-超高效液相色谱-串联质谱测定人体血浆中的百草枯残留

Determination of Paraquat in Human Plasma Using Liquid-Liquid Extraction and Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry

[目的]百草枯使用量大、毒性强,人们因意外或自杀摄入而中毒死亡的风险大。了解百草枯中毒后的血药浓度,对病人拯救和预后至关重要。[方法]建立了超高效液相色谱-串联三重四极杆质谱快速测定人体血浆中百草枯残留的方法。样品先经乙腈萃取、沉淀蛋白后,以硅烷醇基完全裸露的BEH HILIC色谱柱为分离柱、经电喷雾正离子源离子化、多反应监测,添加回收标准曲线外标法定量。[结果]在0.05~4.00 mg/L范围内,百草枯的质量浓度与对应的色谱峰面积间呈良好的线性关系,相关系数为0.9989,检出限为0.01 mg/L,定量限为0.03 mg/L,在0.03~2.00 mg/L的添加水平下,百草枯的回收率在71.5%~95.1%之间;相对标准偏差在4.8%~9.1%之间。[结论]该方法通过HILIC柱硅烷醇基对百草枯的特异性作用,解决了UPLC-MS法建立中"百草枯柱效提升"和"仪器污染"的矛盾问题,具有分析时间短、准确度好、灵敏度高等优点,适用于人体血浆中百草枯残留测定。

[Aims] Paraquat is one of a widely utilized herbicide with high toxicity so that the death risk of paraquat poisoning is greater because of accidental or suicidal ingestion. Understanding the paraquat concentration in plasma after poisoning is crucial important for patient rescue and prognosis. Therefore, this study aims to develop a simple and sensitive ultra-performance liquid chromatography-tandem mass spectrometry for determination of paraquat in plasma samples. [Methods] The best conditions for analysis were as follow: plasma sample was treated by liquid extraction with acetonitrile for protein precipitation and paraquat uptake;furthermore, the mobile phase consisting of acetonitrile and ammonium formate was used under isocratic elution to isolate paraquat from impurities with BEH HILIC column as the separator. The mass spectrometric detection was conducted in positive electrospray ionization with multiple reaction monitoring mode. The quantification of paraquat was performed using the matrix matched/external standard method. [Results] With the established method, an excellent linear relationship between chromatographic peak area and mass concentration of paraquat was obtained in the range of 0.05-4.00 mg/L with the correlation coefficient of0.9989. Moreover, the detection limit and the quantitation limit sensitively reached 0.01 and 0.03 mg/L, respectively.Under the fortified level of 0.03-2.00 mg/L paraquat, the satisfactory relative recoveries(71.5-95.1%) were achieved with relative standard deviations of 4.8-9.1%. [Conclusions] During the establishment of UPLC-MS method, the contradiction between‘ paraquat column efficiency’and ‘Instrument pollution’was worked out by strengthening the specific forces between paraquat and silanol group of HILIC column. This method is rapid, accurate and sensitive, and is suitable for the analysis of paraquat residues in plasma.