Drug abuse is a global menace in the society. Strict measures are planned and effectuated to dismantle this crime yet a large number of cases of narcotics drugs are seized and referred to forensic science laboratories for analysis. Over the past few years, the misuse of precursor chemicals has increased substantially. Examination of these precursor chemicals, especially ephedrine and its analogues, is a major task for forensic analysts. Though gas chromatography–mass spectrometry (GC–MS) is a well-established technique, it dwindles in the identification of the analogues of ephedrine as they have similarity in molecular weight and structure. The analysis involves time-consuming extraction and derivatization process in sample preparation when used for the identification of isomers. The present paper describes a use of high-performance thin-layer chromatography coupled with mass spectrometry (HPTLC–MS) for the purpose. This technique requires minimum sample preparation; it is a quick and easy methodology with no derivatization and gives a conclusive result for the separation and identification of ephedrine analogues. The drug samples were dissolved in methanol and spotted on Si₆₀ F₂₅₄ thin-layer chromatography (TLC) plate. Good separation of ephedrine from a mixture of ephedrine, pseudoephedrine, and phenylpropanolamine was achieved using the solvent system n-butyl acetate–acetone–n-butanol–5 M ammonia–methanol (4:2:2:1:1, v/v). The separated spot on the TLC was subjected to MS, which identified ephedrine with confirmation.

滥用毒品是社会的全球性威胁。已计划并采取了严厉措施来消除这一罪行，但仍查获了大量麻醉药品案件，并转交法医科学实验室进行分析。在过去的几年中，前体化学品的滥用已大大增加。对这些前体化学品，尤其是麻黄碱及其类似物的检查，是法医分析师的一项主要任务。尽管气相色谱-质谱法（GC-MS）是一项行之有效的技术，但由于麻黄碱类似物的分子量和结构相似，因此在鉴定麻黄碱类似物方面却有所减少。当用于异构体的鉴定时，分析涉及样品制备中耗时的提取和衍生化过程。为此目的，本白皮书介绍了结合高效质谱（HPTLC-MS）的高性能薄层色谱的使用。此技术需要最少的样品准备；它是一种无需衍生化的快速简便的方法，可为麻黄碱类似物的分离和鉴定提供最终结果。将药物样品溶解在甲醇中并点在Si上₆₀ F ₂₅₄薄层色谱（TLC）板。使用溶剂系统乙酸正丁酯-丙酮-正丁醇-5 M氨水-甲醇（4：2：2：1：1，v / v）可将麻黄碱与麻黄碱，伪麻黄碱和苯丙醇胺的混合物很好地分离）。在薄层色谱上分离的斑点进行了质谱分析，经鉴定鉴定为麻黄碱。