Marcelo M C A, Mariotti K C, Ferrão M F, Ortiz R S
Instituto de Química, Universidade Federal do Rio Grande do Sul, Brazil.
Faculdade de Farmácia, Universidade Federal do Rio Grande do Sul, Brazil.
Forensic Sci Int. 2015 Jan;246:65-71. doi: 10.1016/j.forsciint.2014.11.011. Epub 2014 Nov 22.
In this article, five hundred and thirteen cocaine seizures of the State of Rio Grande do Sul (Brazil) were analyzed by Fourier transform infrared spectroscopy (FT-IR) in the fingerprint region (1800-650 cm(-1)) to profiling and evaluate the pharmaceutical products used as adulterants. Hierarchical cluster analysis (HCA) and principal component analysis (PCA) were used to identify patterns among the samples whereas partial least square discriminant analysis (PLS-DA) and support vector machines discriminant analysis (SVM-DA) were used to classification the cocaine between base and salt. Spectra of standard solid mixtures of cocaine (salt and base), phenacetin, lidocaine and caffeine were used associated with PCA to predict qualitatively the profile of cocaine seizure. In HCA and PCA, salt and base group were formed correctly. Accordingly with predicted profile of the salt samples, they were majority adulterated with caffeine and lidocaine whereas base cocaine was adulterated only with phenacetin. In the discrimant analysis, all methods have classified the cocaine samples correctly with sensitivity and specificity equal to one between salt and base.
在本文中，对巴西南里奥格兰德州的513起可卡因缉获物进行了指纹区（1800 - 650 cm(-1)）的傅里叶变换红外光谱（FT-IR）分析，以对用作掺假剂的药品进行剖析和评估。采用层次聚类分析（HCA）和主成分分析（PCA）来识别样本中的模式，而偏最小二乘判别分析（PLS-DA）和支持向量机判别分析（SVM-DA）则用于对可卡因的碱和盐形式进行分类。可卡因（盐和碱）、非那西丁、利多卡因和咖啡因的标准固体混合物光谱与PCA结合使用，以定性预测可卡因缉获物的特征。在HCA和PCA中，盐和碱组被正确形成。根据盐样本的预测特征，它们大多被咖啡因和利多卡因掺假，而可卡因碱仅被非那西丁掺假。在判别分析中，所有方法都正确地对可卡因样本进行了分类，盐和碱之间的灵敏度和特异性均等于1。
