Identificação de cocaína e seus adulterantes em impressões digitais latentes reveladas com tiocarbamoil pirazol utilizando molde de silicone

Abstract

This study comprises the application of a silicone mold simulating the papillary lines present in the distal phalanx connected to an experimental protocol for developing fingerprints with residues of cocaine and some of its adulterants. Substances excreted by human skin such as squalene and in particular palmitoleic, myristic, lauric, octadecanoic and decanoic fatty acids were simulated using synthetic esters that were later made available for application to the mold. Four samples containing one of them residues of cocaine, another of lidocaine, a third of caffeine and a fourth sample containing a mixture of residues of caffeine, lidoaine and benzocaine were added onto glass surfaces. Subsequently, the silicone mold moistened by a mixture of squalene and fatty acids was pressed onto the surfaces and simulated fingerprints were developed with thiocarbamoyl pyrazole developer. After development, the material was traced and extracted by washing with methanol for analysis by Gas Chromatography coupled with Mass Spectrometry (CG/MS) allowing the identification of cocaine, lidocaine and caffeine residues present in latent papillary prints. Still, the material resulting from the glass surface with residue from the mixture of caffeine, lidocaine and benzocaine was subjected to analysis by Liquid Chromatography coupled with Mass Spectroscopy (LC/MS/MS) where the presence of adulterants, of the substances used to simulate, was identified. the material excreted from the distal phalanx (scalene and fatty acid esters) and also from the developer powder.