The aim of the study was to develop an algorithm for directed analysis of diphenhydramine in biological extracts from urine and blood using a unified method of HPLC research. Materials and methods. The extraction of diphenhydramine was carried out with chloroform at pH 9.0. The extracts were purified from impurities by a combination of TLC and extraction with hexane. TLC purification and identification of diphenhydramine were carried out under optimal conditions: organic solvents systemschloroform-methanol (90:10); methanol; methanol-25 % solution of ammonium hydroxide (100:1.5) and chromatographic plates-Sorbfil PTLC-AF-A, Sorbfil PTLC-P-B-UV. For the detection of diphenhydramine, the most sensitive location reagents were used-UV light (λ=254 nm) and Dragendorff reagent in the modification of Mounier. HPLC analysis was carried out on a microcolumn liquid chromatograph "Milichrome A-02" in conditions: reversed-phase variant, column with non-polar sorbent Prontosil 120-5 C 18 AQ, 5 μm; mobile phase in the mode of linear gradient-from eluent А (5 % acetonitrile and 95 % buffer solution) to eluent B (100 % acetonitrile) as during 40 min. The flow rate of the mobile phase has been formed 100 μl/min, injection volume-4 μl. Multichannel detection of the substance was carried out using a UV spectrophotometer at 210, 220, 230, 240, 250, 260, 280 and 300 nm; the optimal value of column temperature-37-40 С and pressure of pump-2.8-3.2 MPa. Results and its discussion. Extraction, purification, identification and quantitative determination of diphenhydramine were carried out according to the developed methods. It is established that when isolating diphenhydramine from blood according to the developed methods it is possible to allocate 34.2-38.4 % of substance   5.69 %, 2.04 % RSDx     and from urine-55.8-60.5 % of substance   3.91 %, 1.40 %. RSDx     Conclusions. An algorithm has been developed for directed analysis of diphenhydramine in biological extracts from urine and blood using a unified HPLC method. Statistical processing of the experimental results indicates the reliability and reproducibility of the technique

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Introduction. Аlfuzosin hydrochloride -(RS)-N-[3-[(4-Amino-6,7-dimethoxyquinazolin-2-yl)-methyl-amino]propyl] tetrahydrofuran-2-carboxamide hydrochloride -belongs to the group of α1-adrenoblockers and is used in medical practice for the treatment of arterial hypertension and prostatic hypertrophy [1,2]. When applying аlfuzosin, there are possible side effects: dry mouth, nausea, headache, dizziness, weakness, drowsiness, tachycardia, angina symptoms, allergic reactions. In case of overdose or self-medicate with аlfuzosin the cardiovascular system is affected, the activity of the central nervous system is suppressed, respiratory system is broken.The previously developed methods of HPLC analysis of аlfuzosin hydrochloride are distinguished by the use of different chromatographic conditions, which are based on the individual properties of investigated substance. Method of identification and quantification of аlfuzosin by HPLC method in the application of various detection options in various matrices was carried out using different sorbents, composition of moving phases, buffer solutions in isocratic and gradient elution modes [3,4].An important stage for further research of alfuzosin and other antihypertensive drugs is the development of a unified HPLC method and the creation of databases by the parameters of identification and quantitative determination of analytes. The results of research on a unified HPLC method can be recommended for the introduction into the practice of the bureau of forensic examination, toxicological centers, clinical laboratories regarding the study of medicinal substances in biological objects.Aim. The identification and quantification of alfuzosin, when using unified conditions HPLC, suitable for studies of pharmaceuticals and biological objects.Materials and method. Investigations of alfuzosin by HPLC-method were performed on the basis of scientific-production association "Analytics" (Kharkov).

Topicality. Сlemastine fumarate (tavegil)-1-methyl-2 [2-α-methyl-p-chlorobenzhydryloxy)-ethyl]-pyrrolidine fumarate is the first generation H1-histamine receptor blocker. Сlemastine fumarate selectively inhibits histamine H1 receptors and reduces capillary permeability. The drug has a pronounced anti-allergic and antipruritic effect. Clemastine prevents the development of vasodilation and the smooth muscle contraction induced by histamine. Сlemastine fumarate has an isignificant anticholinergic activity, causes sedation. The drug is used to treat pruritus in psoriasis, multiple sclerosis and optic neuritis. Clemastine is characterized by the following side effects: increased fatigue, drowsiness, sedation, weakness, lethargy, impaired coordination of movements; nausea, vomiting, decreased blood pressure, palpitations, hemolytic anemia, skin rash, anaphylactic shock. In case of an overdose, the drug has a neurotoxic effect, which manifests itself in impaired consciousness with the development of generalized anticholinergic convulsive syndrome. The urgent task for monitoring the treatment effectiveness of the population with сlemastine fumarate and diagnosis of drug intoxication is the choice of highly sensitive and selective research methods of its analysis in pharmaceuticals and biological matrices during the treatment. Aim. To develop an algorithm for directed analysis of clemastine in biological extracts from the blood using a unified method of the HPLC research. Materials and methods. The extraction of clemastine was performed with chloroform at Ph 9.0. The extracts were purified from impurities by a combination of TLC and extraction with hexane. The TLC purification and identification of clemastine were carried out under optimal conditions: the system of organic solvents – methanol – 25 % solution of ammonium hydroxide (100 : 1.5) and chromatographic plates – Sorbfil PTLC-AF-A, Rf сlemastine = 0.60 ± 0.03. To detect clemastine, the most sensitive location reagents were used –UV light (λ  = 254 nm) and Dragendorff’s reagent modified by Mounier. The chromatographic analysis was performed on a “Milichrome A-02” microcolumn liquid chromatograph (EkoNova, Closed Joint-Stock Company, Russia) under standardized HPLC conditions: the reversed-phase variant using a metal column with a non-polar absorbent Prontosil 120-5C 18 AQ, 5 μm; the mobile phase in the linear gradient mode – from eluent А (5 % acetonitrile and 95 % buffer solution – 0.2 М solution of lithium perchlorate in 0.005 М solution of perchloric acid) to eluent B (100 % acetonitrile) for 40 min. Regeneration of the column was conducted for 2 min with the mixture of solvents; the flow rate of the mobile phase was 100 μl/min, the injection volume – 4 μl. The multichannel detection of the substance was performed using a two-beam multi-wave UV spectrophotometer at 8 wavelengths of 210, 220, 230, 240, 250, 260, 280, and 300 nm; the optimal value of the column temperature – 37-40 °С and the pump pressure – 2.8-3.2 MPa. Results and discussion. Isolation of clemastine from the blood was performed according to the method developed, including the extraction with chloroform at pH 9.0; the extraction purification of extracts with hexane from impurities; the TLC purification and identification of clemastine. Using the unified HPLC method clemastine was identified by retention parameters and spectral ratios. For the quantitative determination, a calibration graph or the straight line equation corresponding to this graph were used. The results obtained indicated the reliability and reproducibility of the method. It was found that the relative uncertainty of the average result in the analysis of clemastine in the blood was ε = ± 4.63 %, the relative standard deviation of the average result was RSDx = 1.67 %. Conclusions. Clemastine was extracted with chloroform at pH 9.0 from the blood. Purification of extracts from co-extractive compounds was performed by combining TLC and extraction with hexane. It has been found that when isolating сlemastine from the blood according to the methods developed it is possible to determine 36.05-39.55 % of the substance (ε = ± 4.63 %, RSDx = 1.67 %). The method of TLC purification and identification of сlemastine in biogenic extracts was tested under the optimal conditions: the system of organic solvents – methanol – 25 % solution of ammonium hydroxide (100 : 1.5), the use of reagents – UV light, Dragendorff’s reagent modified by Mounier, Rf сlemastine = 0.60 ± 0.03 (Sorbfil PTLC-AF-A). The unified HPLC method for identification and quantification of сlemastine was tested in biogenic extracts from the blood according to the algorithm of the directed analysis developed. It has been found that сlemastine can be identified by the retention time – 25.997-26.011 min; the retention volume – 2599.7-2601.1 μl; spectral ratios – 0.741; 0.536; 0.096; 0.023; 0.027; 0.005; 0.003. The сlemastine content was determined by the equation S = 0.15 · 10-3 С + 0.14 · 10-3; the correlation coefficient was equal to 0.9998. Chromatographic methods can be recommended for implementation in practice of the Bureau of Forensic Medical Examination, poison control centers, clinical laboratories regarding the study of medicinal substances in biological objects.

Introduction. amino] propoxy] benzene acetamide -β-adrenoceptor blocking agent is used to treat stenocardia, arterial hypertension, tachycardia, myocardial infarction [1,2]. Atenolol can cause bradycardia, hypotension, depression, hallucinations, allergies and as a result of overdose and self-treatment, it can cause intoxication of the organism and the lethal effects [3,4].For therapeutic monitoring during the treatment of patients, for the study of biological objects on atenolol as a result of intoxication and lethal consequences, the use of highly sensitive, rapid and effective methods of analysis is important.The most common chromatographic methods for analysis of atenolol are gasliquid chromatography (GLC) [3], high performance liquid chromatography (HPLC) [3,5], gas chromatography-mass spectrometry (GC-MS) [6]. The previously developed methods of HPLC analysis of atenolol are distinguished by the use of different chromatographic conditions, which are based on the individual properties of investigated substance.Аn important stage for the further research of medicinal substances and their mixtures in biological objects is the development of a unified HPLC method and the creation of databases by the parameters of identification and quantitative determination of analytes.Purpose of workthe development of analysis of atenolol by unified HPLC method.Materials and methods of research. Chromatographic analysis was carried out on a microcolumn liquid chromatograph "Milichrome A-02" (EkoNova, Closed Joint-Stock Company, Novosibirsk, Russia) according to the unified HPLC methodology developed by the author -Baram G.Y. using standardized HPLC conditions: reversed-phase variant with using of metallic column with non-polar absorbent Prontosil 120-5C 18 AQ, 5 μm; mobile phase in the mode of linear gradientfrom eluent А (5 % acetonitrile and 95% buffer solution -0,2 М solution of lithium perchlorate in 0,005 М solution perchloric acid) to eluent B (100% acetonitrile) as during 40 min. Regeneration of column has been conducted during 2 min with