STUDY OF THE TERMS OF DETECTION OF CERTAIN DRUGS IN URINE AND HAIR TO EXCLUDE UNRELIABLE RESULTS DURING CLINICAL LABORATORY DIAGNOSTICS OF BIOLOGICAL OBJECTS

Introduction. When using immunochromatographic test strips for preliminary urine tests of examined persons for the fact of using psychoactive substances, there is a possibility of false positive results. One of the possible approaches to solving the problem of false positive results of chemical and toxicological studies, including cross-reactions in the drug administration, is hair analysis. The purpose of this work is to study the timing of detection of certain drugs (mebeverine, phenylephrine, sertraline, chlorpromazine) in urine and hair to exclude unreliable results of clinical laboratory diagnostics. Material and methods. Modeling of drug administration (phenylephrine, mebeverine, sertraline, aminazine) was carried out using laboratory animals - guinea pigs. The study of extracts from biological objects was carried out on a gas chromatograph with a mass-selective detector Agilent Technolo-gies (USA) 7890 A/5977 MSD, as well as by the HPLC-MS/MS method on a modular liquid chromatograph Nexera XR with a tandem mass spectrometer LCMS-8050 (Shimadzu, Japan). Results. The dynamics of the content of the studied medicinal substances in the urine within 168 hours after a single dose of daily dosage, the max-imum detection time of these substances: mebeverine and chlorpromazine for more than 7 days, sertraline and phenylephrine for no more than 5 days were studied. The features of the accumulation of the studied medicinal substances in the hair are determined. Mebeverine and chlorpromazine accumulate in significant amounts in the hair when ingested chronically, about 100 ng/mg and 80 ng/mg, respectively, and are also identified in statis-tically significant amounts 56 days after chronic use is stopped. Phenylephrine and sertraline accumulate in the hair in trace amounts, at a level of 2-5 ng/mg, and are also detected in trace amounts 28 days after discontinuation of administration. Conclusion. A systematic study of the dynamics and level of accumulation of toxicants in the hair tissue on the example of the studied drugs (mebeverine, phenylephrine, sertraline and chlorpromazine) showed results consistent with the data of the literature, and indicating that the dynamics of the accumulation and the level of accumulation of drugs in the hair structure depends on the physicochemical and pharmacological properties of the substance itself. Studies have shown that substances accumulate in the hair structure only in the form of native molecules, which makes it possible to recommend this biological material to solve the issue of cross-reactions of medicinal substances during the preliminary stage of clinical laboratory diagnostics with immunochromatographic test strips.