Battu C, Marquet P, Fauconnet A L, Lacassie E, Lachâtre G
Department of Pharmacology and Toxicology, University Hospital, Limoges, France.
J Chromatogr Sci. 1998 Jan;36(1):1-7. doi: 10.1093/chromsci/36.1.1.
A specific, sensitive, and rapid procedure for the screening of 21 amphetamine-related compounds in urine is developed using solid-phase microextraction (SPME) and gas chromatography-mass spectrometry. Very clean extracts are obtained in one step with SPME using silica fibers coated with a 100-micron polydimethylsiloxane stationary phase. Temperature, time, pH, and salt saturation are optimized to obtain consistent extraction. An excellent chromatographic separation of the underivatized analytes is obtained with a specially treated nonpolar capillary column (Supelco PTA-5, 30 m x 0.32-mm i.d., 0.5-micron film thickness) dedicated to amino compounds. Selected ion monitoring of three fragments per analyte and one for each of the three deuterated internal standards elicits a high selectivity and detection limits between 1 and 50 ng/mL (i.e., low enough to verify positive results obtained with immunochemical assays). The method is linear in a narrow range (from the detection limit up to 500 ng/mL) when all the amphetamines are assayed together but shows a good linearity up to 2000 ng/mL when the molecules are determined individually. Repeatability is not satisfactory for all compounds but could probably be improved by strictly controlling the extraction time (e.g., by automating the whole procedure using an autosampler). The use of SPME reduces the interference due to urinary low-volatility organic compounds and avoids the risks related to the use of organic solvents. To our knowledge, this technique is the first one allowing the sensitive determination of such a number of amphetamine analogs.
采用固相微萃取（SPME）和气相色谱 - 质谱联用技术，开发了一种用于筛查尿液中21种苯丙胺类相关化合物的特异性强、灵敏度高且快速的方法。使用涂覆有100微米聚二甲基硅氧烷固定相的硅胶纤维，通过SPME一步即可获得非常纯净的提取物。对温度、时间、pH值和盐饱和度进行了优化，以实现一致的萃取效果。使用专门处理的用于氨基化合物的非极性毛细管柱（Supelco PTA - 5，30 m×0.32 mm内径，0.5微米膜厚），对未衍生化的分析物实现了出色的色谱分离。对每种分析物的三个碎片以及三种氘代内标物中的每一种各一个碎片进行选择离子监测，具有高选择性，检测限在1至50 ng/mL之间（即低到足以验证免疫化学分析获得的阳性结果）。当一起检测所有苯丙胺类化合物时，该方法在较窄范围内（从检测限到500 ng/mL）呈线性，但当单独测定这些分子时，线性良好，可达2000 ng/mL。并非所有化合物的重复性都令人满意，但通过严格控制萃取时间（例如，使用自动进样器实现整个过程的自动化）可能会有所改善。SPME的使用减少了尿液中低挥发性有机化合物的干扰，并避免了与使用有机溶剂相关的风险。据我们所知，这项技术是首个能够灵敏测定如此多种苯丙胺类似物的技术。
