尿中苯丙胺、甲基苯丙胺、MDA和MDMA的固相微萃取和GC/MS/SIM测定

目的研究固相微萃取(SPME)用于尿中苯丙胺(AMP)、甲基苯丙胺(MET)、3,4-亚甲二氧基苯丙胺(MDA)和3,4-亚甲二氧基甲基苯丙胺(MDMA)的提取。方法样品调节至碱性和用盐饱和后用顶空SPME,内标为MET-d5。萃取纤维为100μm聚二甲基硅氧烷(PDMS)。用气质联用选择离子检测(GC/MS/SIM)。结果0.2μg/ml加标尿样,AMP、MET、MDA和MDMA的富集倍数分别为22,60,13和47。检出限(S/N=3)为0.4～9.5ng/ml。线性范围为0.05～1μg/ml。0.2、0.5和1.0μg/ml加标尿样,相对回收率77.9%～112.4%,变异系数2.7%～18.0%(n=5)。用该方法分析5个案件样品,和常规液液萃取结果接近。结论顶空SPME法用于尿中AMP、MET、MDA和MDMA等化合物的分析,无需有机溶剂,富集效率高,提取-富集-进样一体化,简单方便实用。

Determination of amphetamine, methamphetamine, MDA and MDMA in urine samples by solid-phase microextraction and gas chromatography-mass spectrometry in selected ion monitoring

Objective To develop a solid-phase microextraction (SPME) method to extract amphetamine (AMP), methamphetamine (MET), 3,4-methylene-dioxyamphetamine (MDA) and 3,4-methylenedioxymethamphetamine (MDMA) from urine. Method The sample was alkalized and saturated with sodium chloride prior to SPME. MET-d 5 was used as the internal standard (IS). The analytes and IS were absorbed onto the 100-μm polydimethylsiloxane(PDMS)fiber with Supelco manual assembly. The analytes were detected by gas chromatography-mass spectrometry in selected ion monitoring (GC/MS/SIM). Results The enrichment factors were 22, 60, 13 and 47 for AMP, MET, MDA and MDMA respectively at 0.2 μg/ml spiked levels. Limits of detection (S/N=3) were between 0.4 ng/ml and 9.5 ng/ml. The linearity was in range of 0.05~1μg/ml. For 0.2, 0.5 and 1.0 μg/ml spiked levels of the analytes, the relative recoveries were in range of 77.9%~ 112.4% with coefficients of variation between 2.7% and 18.0% (n=5). Five urine samples collected from the cases were analyzed by this method, and the results were in good agreement with those as detected by liquid-liquid extraction. Conclusion The method developed is solvent-free and highly efficient in eorichment, which is simple, convenient and practical by combining extraction, enrichment and injection in one step.