Nagai T, Kamiyama S, Kurosu A, Iwamoto F
Department of Legal Medicine, Dokkyo University School of Medicine, Tochigi, Japan.
Nihon Hoigaku Zasshi. 1992 Aug;46(4):244-53.
In order to identify optical isomers (d and l-) of methamphetamine (MAMP), GC-MS analysis using optically resolvable reagent of N-trifluoroacetyl-L-prolyl chloride (L-TPC) and HPLC analysis using chiral cellulose-based columns were compared. In analysis of d- or l-MAMP (M) of TPC (T) derivatives by the GC-MS, contrary to the expectation that only d(M)-L(T) or l(M)-L(T) could be detected chemically, two diastereomers of d(M)-L(T) and d(M)-D(T) for d-MAMP and two of l(M)-L(T) and l(M)-D(T) for l-MAMP were demonstrated respectively. This results was attributed to a small percentage of D-TPC present in L-TPC. For racemic (dl)-MAMP, none of these four isomers could be individually isolated, and they were detected as two overlapping peaks. In the HPLC analysis using chiral columns, d- and l-isomers of MAMP and amphetamine (AMP) could be clearly isolated with merely one analytical procedure, and the l/d ratio was possible to calculate with facility. From the rats urine administered d- or l-MAMP, only the corresponded optically active form of the administered drug was detected, and when racemic (dl)-MAMP was administered, d-MAMP, l-MAMP and their metabolites AMP were distinctly detected. The l/d ratio calculated from amount of MAMP and AMP excreted in rat urine within 24 hr was not in accordance with that of the administered dl-MAMP (l/d = 1.01): the l/d ratio was 0.45 for MAMP and 0.58 for AMP, and 0.50 for the total of MAMP and AMP. The similar results were observed in case of racemic (dl)-AMP. From several human specimens obtained from the cadavers dead by MAMP poisoning, only d-MAMP and the metabolite d-AMP were detected, and neither l-MAMP or l-AMP were demonstrated. In particular, a high concentration of d-MAMP was detected in gastric contents, brain, lung and liver. From the MAMP powder in possession, only d-MAMP was detected. These results suggest that this chiral column-HPLC procedure could be applied to medicolegal practice and forensic scientific investigation.
为了鉴别甲基苯丙胺（MAMP）的旋光异构体（d型和l型），比较了使用可旋光拆分试剂N-三氟乙酰-L-脯氨酰氯（L-TPC）的气相色谱-质谱联用（GC-MS）分析以及使用手性纤维素基柱的高效液相色谱（HPLC）分析。在通过GC-MS分析TPC（T）衍生物的d-或l-MAMP（M）时，与仅能化学检测到d（M）-L（T）或l（M）-L（T）的预期相反，分别证明了d-MAMP有d（M）-L（T）和d（M）-D（T）两种非对映异构体，l-MAMP有l（M）-L（T）和l（M）-D（T）两种非对映异构体。该结果归因于L-TPC中存在少量的D-TPC。对于外消旋（dl）-MAMP，这四种异构体均无法单独分离，它们被检测为两个重叠峰。在使用手性柱的HPLC分析中，仅通过一个分析步骤就能清晰分离MAMP和苯丙胺（AMP）的d型和l型异构体，并且能够轻松计算l/d比值。从给予d-或l-MAMP的大鼠尿液中，仅检测到所给药的相应旋光活性形式的药物，而给予外消旋（dl）-MAMP时，能明显检测到d-MAMP、l-MAMP及其代谢产物AMP。根据大鼠尿液中24小时内排出的MAMP和AMP量计算出的l/d比值与所给药的dl-MAMP的l/d比值（l/d = 1.01）不一致：MAMP的l/d比值为0.45，AMP的l/d比值为0.58，MAMP和AMP总量的l/d比值为0.50。在外消旋（dl）-AMP的情况下也观察到了类似结果。从因MAMP中毒死亡的尸体获取的几份人体标本中，仅检测到d-MAMP及其代谢产物d-AMP，未检测到l-MAMP或l-AMP。特别是在胃内容物、脑、肺和肝脏中检测到高浓度的d-MAMP。从查获的MAMP粉末中，仅检测到d-MAMP。这些结果表明，这种手性柱-HPLC方法可应用于法医学实践和法医科学调查。
