National Forensic Service, Seoul 158-707, Republic of Korea.
Forensic Sci Int. 2012 Feb 10;215(1-3):175-8. doi: 10.1016/j.forsciint.2011.01.042. Epub 2011 Mar 3.
Impurities in 48 methamphetamine (MA) samples were analyzed by liquid-liquid extraction (LLE) and headspace solid-phase microextraction (HS-SPME) methods. MPS-2 autosampler was used to improve reproducibility of SPME method, and nonadecane (C(19)) diluted with potassium bromide (KBr) powder was used as an internal standard for standardizing retention time. Impurities identified by SPME method showed different patterns compared with LLE method. Non-volatile impurities like methamphetamine dimer were not identified by SPME method, but some volatile impurities like diphenylketone, caprolactam and lots of unknowns were identified only by SPME method. 1-Phenyl-2-propanone (P2P), 1-phenyl-2-propanol and benzylcyanide peaks could be discriminated clearly by SPME method without interference of amphetamine, an artifact originates from MA degradation. Differences in the impurity patterns resulted in different clustering results. When 48 MA samples were classified into 5 LLE and 5 SPME clusters, cross-matching of the clusters resulted in 8 sub-clusters. It shows that combination of the different extraction methods can distinguish the differences which cannot be distinguished by LLE or SPME method alone, and can improve reliability of the profiling results.
采用液液萃取（LLE）和顶空固相微萃取（HS-SPME）方法分析了 48 个甲基苯丙胺（MA）样品中的杂质。MPS-2 自动进样器用于提高 SPME 方法的重现性，并用溴化钾（KBr）粉末稀释的十九烷（C（19））作为内标物来标准化保留时间。与 LLE 方法相比，SPME 方法鉴定出的杂质具有不同的模式。非挥发性杂质，如 MA 二聚体，未通过 SPME 方法鉴定，但一些挥发性杂质，如二苯甲酮、己内酰胺和许多未知物，仅通过 SPME 方法鉴定。1-苯基-2-丙酮（P2P）、1-苯基-2-丙醇和苯甲腈的峰可以通过 SPME 方法清晰地区分，而不受安非他命（MA 降解产物）的干扰。杂质模式的差异导致聚类结果不同。当将 48 个 MA 样品分为 5 个 LLE 和 5 个 SPME 簇时，簇之间的交叉匹配产生了 8 个子簇。这表明，不同萃取方法的组合可以区分 LLE 或 SPME 方法单独无法区分的差异，并可以提高分析结果的可靠性。
