EXPERT RESEARCH OF MICROQUANTITIES NARCOTIC, PSYCHOTROPIC SUBSTANCES AND PRECURSORS

Abstract

While investigating and prosecuting criminal cases related to illegal drug trade, psychotropic substances and precursors, microobjects found at the scene of crime, as well as on items related to a crime and its participants, assume ever greater evidentiary. In expert practice, narcotic drugs and psychotropic substances often appear as research objects, that are rarely individual compounds. At that greatest difficulties arise while research of substances that are multicomponent systems and mixtures containing a large number of impurity and ballast substances, as well as low concentrations of active substances. So it is difficult to identify the substance that served as the basis for developing a methodology for the investigation of microquantities of narcotic drugs, psychotropic substances and precursors. Despite the fact that chromatographic analysis is the most common method for the analysis of narcotic drugs, psychotropic substances and precursors, currently due to high information content, sensitivity and selectivity in the world practice of forensic chemical and medical examination, methods of gas chromatography-mass spectrometry (GC-MS) and high performance liquid chromatography with mass spectrometric detector (HPLC-MS) become one of the most widely used. The use of the HPLC-MS method is the most optimal while research on narcotic, psychotropic substances and precursors by reducing the time of sample preparation, since there is no need for the stage of reagents evaporation and receipt of derivatives, and also it is appear possible to identify non-volatile substances that cannot be analyzed by GC-MS. As a result of the performed researches a methods for the criminalistic research of microquantities of certain narcotic drugs (heroin, morphine, opium, methamphetamine, cocaine, etc.), psychotropic substances (clonidine, bromazepam, ketazolam, trihexyphenidyl, methaqualone, barbital, etc.), precursors (pseudoephedrine, ephedrine) and a poison such as scopolamine using GC-MS and HPLC-MS.