DEVELOPMENT OF A METHOD FOR ANALYZING MEPHEDRONE AND METHAMPHETAMINE USING GC-MS

567 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz DEVELOPMENT OF A METHOD FOR ANALYZING MEPHEDRONE AND METHAMPHETAMINE USING GC-MS Yuldashev Z.A. Abdukhalikova N.U. Tashkent Pharmaceutical Institute, Tashkent city, Republic of Uzbekistan e-mail: [email protected] https://doi.org/10.5281/zenodo.17344446 Relevance. In recent years, the illegal distribution and abuse of psychoactive substances, particularly drugs belonging to the synthetic amphetamine group, including mephedrone and methamphetamine, have been sharply increasing worldwide. These substances are especially popular among young people due to their strong psychostimulant properties, rapid effects, and relatively low cost. This is creating serious problems not only in socio-economic spheres but also for healthcare and law enforcement personnel. According to data released in 2023 by the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) of the European Union, in Europe alone, more than 6 million people used synthetic stimulants during their lifetime in 2022. According to data from the Ministry of Internal Affairs of the Republic of Uzbekistan, the proportion of crimes related to synthetic drugs has doubled over the past 3 years. Therefore, improving methods for isolating and identifying mephedrone from various objects is currently considered a pressing issue of not only scientific but also practical importance. The aim of the research: to develop a method using gas chromatography-mass spectrometry for analyzing mephedrone and methamphetamine. Methods and materials: the experiments were conducted on a gas chromato-mass spectrometer "XEVO Ta-GC/GC-8890." As a result of the conducted research, the following conditions were selected: a metal capillary column with a length of 30 m and an internal diameter of 0.25 mm, the surface of the inner walls of which is coated with a thickness of 0.25 μm with a 5% solution of phenylmethylsiloxane in dimethylsiloxane; the injector temperature is 200°C; the temperature of the column thermostat rises from 200°C to 300°C at a rate of 10°C/min; the carrier gas - helium, the total gas flow rate is 10 ml/min; the volume of the injected sample is 1 mkl; 1:50 in flow separation mode; analysis time is 25 minutes. To prepare a standard sample solution, each substance was weighed from the standard sample in an accurate amount (5 mg), transferred to a 25 ml volumetric flask, dissolved in 5 ml of 96% ethyl alcohol, and brought to the mark of the flask with the solvent. 1 μl of the sample was taken and sent to the chromatograph column. Results: Under these conditions, peaks with retention times of 5.844 and 3.69 minutes appeared on the chromatogram and were identified as mephedrone and methamphetamine, respectively. In the mass spectrum, ions of the mephedrone fragment with masses of 30, 58, 65, 77, 91, 134 m/z and ions of the methamphetamine fragment with masses of 30, 58, 65, 77, 91, 134 m/z were formed, corresponding to the peaks in the chromatogram. The obtained chromatograms and mass spectra of mephedrone and methamphetamine were compared with the data in the computer library database, and it was established that their structure corresponds to the structure of mephedrone and methamphetamine. Conclusion: As a result of the conducted research work, a method for analyzing synthetic psychostimulants mephedrone and methamphetamine using the GX-MS method was developed for their identification and determination. During the study, the retention times of the peaks on the chromatogram of the standard sample of mephedrone and methamphetamine were 5.84 min and 3.69 568 Volume 5, Issue 10: Special Issue (EJAR) ISSN: 2181-2020 MPHAPP THE 6TH INTERNATIONAL SCIENTIFIC AND PRACTICAL CONFERENCE “MODERN PHARMACEUTICS: ACTUAL PROBLEMS AND PROSPECTS” TASHKENT, OCTOBER 17, 2025 in-academy.uz min, respectively. The chromatographic retention time and fragment ions in the mass spectrum of each substance were determined and compared with international databases, in particular, with the NIST (National Institute of Standards and Technology) and other spectral libraries. The analysis results showed a high degree of consistency with the structural properties of the substances.