HS-SPME-GC/MS联用法测定生物检材中的百草枯

目的建立检测生物检材中百草枯的顶空固相微萃取-气相色谱-质谱联用（HS-SPME-GC/MS）的分析方法。方法尿样中加乙基百草枯作为内标,在氯化镍作催化剂的条件下,用硼氢化钠在碱性条件下进行还原,HS-SPME萃取,提取物经GC/MS分析。全血需先离心,沉淀血细胞提取上清液,再用甲醇沉淀蛋白。最终得到的上清液加内标乙基百草枯,以下操作同尿样。结果尿样和血样中的百草枯的还原产物在1.0μg/mL~100μg/mL范围内线性关系良好,回归方程分别为y=0.0957x-0.0163,r=0.9974（n=6）;y=0.1096x＋0.0871,r=0.9964（n=6）。尿样、血样低、中、高三个质量浓度,RSD值均小于7%。回收率分别为尿样85.49%~100.83%,血样94.72%~99.68%。结论本法操作简便易行、灵敏度高、快速准确。为检测生物检材中的百草枯提供了有效的方法。

Determination of Paraquat in Biological Samples by HS-SPME-GC /MS

Objective To develop a HS-SPME-GC/MS method for determination of paraquat in biological samples. Methods The blood samples were centrifuged first,then using methanol to precipitate proteins,and the supernatant fluid was collected. Ethyl paraquat was added as an internal standard to both blood and urine samples,followed by a reduction procedure under alkaline condition with sodium borohydridenickel chloride. The reduced paraquat was extracted by headspace solid-phase microextraction（ HS-SPME） and analysed by gas chromatography-mass spectrometry（ GC-MS）. Results Excellent linear relationships were obtained within the range of 1. 0μg / mL ~ 100μg / mL,the regression equation was y = 0. 0957x-0. 0163,r = 0. 9974（ n = 6） in urine,y = 0. 1096x ＋ 0. 0871,r = 0. 9964（ n = 6） in blood. The RSD were all less than 7% and recovery was 85. 49% ~ 100. 83% in urine,94. 72% ~ 99. 68% in blood. Conclusion The method is simple,sensitive,accurate and rapid. It is an effective method for determination of paraquat in biological samples.