DETERMINAÇÃO DOS ADULTERANTES CAFEÍNA E LIDOCAÍNA EM AMOSTRAS DE COCAÍNA APREENDIDAS PELA POLÍCIA CIVIL NA BR-262 NO ESTADO DE MATO GROSSO DO SUL NO ANO DE 2019

Abstract

Cocaine is an alkaloid extracted from the leaves of the Erythroxylon coca plant and is one of the most consumed stimulant drugs in the world. Acting directly on the Central Nervous System, it has hallucinogenic, stimulant and anesthetic effects and can cause strong chemical dependence. The seized drugs have a high level of adulteration, with the most common ones present in cocaine being lidocaine and caffeine, which simulate anesthetic and stimulant effects. The two most effective and most used instrumental techniques in forensic analysis for drug identification are Fourier Transform Infrared Spectroscopy (FTIR) and Gas Chromatography coupled to Mass Spectrometry (GC/MS). Therefore, this work aims to analyze the adulterants caffeine and lidocaine in cocaine samples seized by the Civil Police of the State of Mato Grosso do Sul on the BR-262 stretch in 2019, based on data from the Institute of Laboratory Analysis Forensics (IALF) of the General Coordination of Expertise (CGP). The analyzed samples were prepared in methanol in the concentration range of 0.25 to 16 mg L-1 and analyzed by GC/MS. The analytical curve for cocaine, caffeine and lidocaine indicated good linearity, with coefficient of determination (R²) values being, respectively, 0.9991, 0.9994 and 0.9993. The limit of detection (LD) for cocaine, caffeine and lidocaine was 0.25 mg L-1, while the limit of quantification (LQ) was 0.5 mg L-1. In 2019, a total of 1577 samples were analyzed by FTIR, of which 79 showed adulterations with caffeine and lidocaine and 136 showed other types of adulterants. Furthermore, it was noticed that, according to the BR-262 route, the tampering started from the city of Campo Grande. In conclusion, it was possible to evaluate sample adulteration using FTIR analysis data, evaluate some validation parameters by GC/MS and estimate the adulteration route along the BR-262/MS section.