Utilização da espectroscopia Raman na identificação de drogas ilícitas em perícia criminal

Abstract

This paper is a summary of the day to day laboratory forensics. The main drugs seized are described as marijuana, cocaine, crack, ecstasy, among others. Says Brazilian law applied in both the consumption and trafficking of drugs as the classification of these banned substances. Also mentions conventional methods of analysis such as thin layer chromatography and colorimetric and official methods which occur in the coupling of mass spectrometry to gas and liquid chromatography. Laboratory forensics are inundated with examinations and toxicological chemical identification. On the other hand, lack of skilled labor and financial resources are insufficient. How to meet the growing demand for forensic exams is a challenge for the administration. In this respect, this paper proposes the effective use of Raman spectroscopy as a rapid and reliable method of analysis seen by forensic researchers worldwide, in order to make feasible and effective to carry out expert examinations in the field of chemistry cool, considering the disparity between the volume of skills and availability of equipment and personnel. In this paper the proposed technique is used to identify substances that are part of a routine laboratory forensics. Samples taken randomly at different times, different quantities and regions could be identified almost always. Through literature and this study, an identification protocol by Raman substances sent for forensic examination can be prepared by forming a qualified professional to eliminate the bottleneck of the availability of equipment and personnel. This method proved to be faster, easier and economical compared to the official method, which is by gas chromatography-mass spectrometry. Samples of cocaine, crack, ecstasy, solvents and some common solvents were analyzed. All samples crack gave satisfactory results. Samples of cocaine should be analyzed by the official method when the result is negative due to Raman mixture of several solvents that damage the sensitivity of any method that does not operate with a prior separation. Samples of ecstasy tablets also showed a good result, except rare cases where the excessive addition of dyes affect the interpretation of the spectra. To identify solvent technique also proved efficient and has additional advantages such as the ability to analyze the liquid inside the container which was seized. Finally, chemometric tools applied to separate samples of cocaine and crack, which can be laborious using only the results of data analysis equipment.