[The specific features of the distribution of 4-metoxyhydroxybenzene in the organism of the warm-blooded animals suffering lethal intoxication]

[Study of 2,6-di(propan-2-yl)phenol stability in biomaterial]

The aim of this study is to research the stability of 2.6-di(propan-2-yl)phenol in biomaterial. GC-MS (column DB-5MS EVIDEX (25 m×0.2 mm); stationary liquid phase of 5%-phenyl-95% dimethylpolysiloxane), TLC (Sorbfil plates, mobile phase of hexane-diethyl ether (9:1) and spectrophotometry (solvent medium - 95% ethanol) were used as methods of analysis. 2.6-di(propan-2-yl)phenol was isolated from the biomatrix (liver tissue) by infusion with a mixture of ethyl acetate-acetone (7:3). The analyte was purified by combining extraction (water-ethyl acetate system) and semi-preparative chromatography on a column of silica gel L 40/100 µm, eluent - hexane-acetone (7:3). It was found that at -22 °C, 0 °C, 12 °C, 20 °C and 30 °C 2.6-di(propan-2-yl)phenol can be present in the liver tissue for 119, 98, 70, 56 and 42 days, respectively. The possibility of mathematical description of analyte decomposition dynamics in biomaterial (liver tissue) at the considered temperatures on the basis of hyperbola equation has been studied. The experimentally calculated coefficients in the hyperbola equation (k_m) for temperatures -22 °C, 0 °C, 12 °C, 20 °C and 30 °C are equal to 1823, 1130, 697, 510, and 255, respectively. The dependence k_m on the conserving temperature (t^о) was educed. The equation for the description of dependence is offered: k_m=30.61∙(50-t^o)-402.39. It is shown that this equation can be the basis for prediction of 2.6-di(propan-2-yl)phenol stability in biomaterial (liver tissue) in the temperature range from -22 °C to 30 °C.

[Development of 2,4,6-trinitrophenol examination methods to evaluate the features of its distribution in warm-blooded animals]

THE OBJECTIVE

Is to study a 2, 4, 6-trinitrophenol (2.4,6-TNP) distribution in warm-blooded animals using physical chemical analysis methods after intragastric injection of toxicant. The methods of thin-layer chromatography, spectrophotometry and high-efficient liquid chromatography were used in the study process. Four-months-old rats of the Wistar line (males) were considered as a model of warm-blooded organisms. The investigated substance in amount of three-times LD50 was intragastrically injected in the aqueous-suspension state. 2.4,6-TNP was isolated by a mixture of acetone-acetonitrile (1:1) in a double (by 0.5 of hour) infusing mode from the bioactive matrix of experimental animals, sustaining the mass ratio of isolated agent to bioactive matrix equaled to 2:1. Purification and preliminary identification of analyte were conducted on «Sorbfil» plates (mobile phase - acetone - chloroform (7:3)), confirming identification - by absorption in dimethylformamide medium and by retention time in column (64×2 mm) of «Separon C-18» sorbent during elution by acetonitrile-water (2:8) mixture. The evaluation of 2, 4, 6-trinitrophenol quantitative content by optical density of dimethylformamide solution of analyte at 379 nm was carried out. The analyte in unchanged form was found in blood, parenchymatous and hollow organs, their contents and blood of experimental animals. The highest content of 2.4,6-TNP (mg/100 gr) was revealed in gastric content (149.88±22.70), gastric tissue (97.89±4.86), blood (15.91±0.90) and muscles (10.87±1.91).

[Study of the stability of 2-methoxy-4-(2-propenyl) hydroxybenzene in biological material]

The purpose of this work is to study the stability of 2-methoxy-4-(2-propenyl)hydroxybenzene [2-MO-4-(2-P)HOB] in biological material. For analysis, gas chromatography-mass spectrometry (GC-MS) was used: column DB-5MS EVIDEX (25 m × 0.2 mm) with a stationary phase of 5%-phenyl-95%-dimethylpolysiloxane; thin layer chromatography (TLC): Sorbfil plates, hexane-dioxane-propanol-2 mobile phase (40:5:1) and UV spectrophotometry (solvent - 95% ethanol). 2-MO-4-(2-P)HOB was isolated from the biomatrix (liver tissue) by infusion with a mixture of ethyl acetate-acetone (7:3). Purification of the analyte was carried out by combining extraction (water-ethyl acetate system) and semi-preparative column chromatography [sorbent - silica gel L 40/100 μm, eluent - hexane-dioxane (8.5:1.5)]. It was established that at -22 °C, 4 °C, 12 °C, 20 °C and 30 °C 2-MO-4-(2-P)HOB is stored in the liver tissue for 385, 357, 301, 245 and 217 days, respectively. We studied the possibility of mathematical description of the dynamics of analyte decomposition in a biomaterial (liver tissue) at the indicated temperatures using the hyperbolic equation. The coefficients in the hyperbola equation (k_av), calculated according to the results of the experiment, for temperatures of -22 °C, 4 °C, 12 °C, 20 °C and 30 °C amounted to 6223, 3036, 2387, 1903 and 932, respectively., which is described by the equation: kav=101.19∙(50-to)-1272.78. It was established that on the basis of this equation it is possible to predict the nature of the stability of 2-MO-4-(2-P)HOB in the biomaterial (liver tissue) at temperatures in the range from -22 °C to 30 °C.

[Development of methods for determining and studying the persistence of 2,4-dimethylhydroxybenzene and 2,6-dimethylhydroxybenzene in biological material]

OBJECTIVE

To study the features of the determination and preservation of 2.4-dimethylhydroxybenzene and 2.6-dimethylhydroxybenzene in biological material. Extraction, semi-preparative chromatography, TLC, GC-MS and UV spectrophotometry are considered as methods of analysis. The 2.4- and 2.6-dimethylhydroxybenzenes were isolated from the biomaterial by double infusion (30 minutes each) with a mixture of ethyl acetate-acetone (7: 3) at a weight ratio of the insulating liquid and biomaterial of 2:1. Purification was carried out by extraction and chromatography in a semi-preparative (190×10 mm) column of silica gel L 40/100 µm using the eluent hexane-dioxane-propanol-2 (80: 5: 1). Analytes were determined by TLC (Sorbfil plates, mobile phase hexane-dioxane-propanol-2 (120: 5: 1)), GC-MS (DB-5MS EVIDEX column (25 m × 0.2 mm) with a stationary phase (5%-phenyl) - methylpolysiloxane), UV spectrophotometry (solvent - 95% ethanol). The developed methods for the determination of 2.4- and 2.6-dimethyl derivatives of hydroxybenzene in biomaterial (liver tissue) are validated according to the criteria of linearity, selectivity, correctness and precision. The study of the dynamics of decomposition of 2.4- and 2.6-dimethyl hydroxybenzene derivatives in model mixtures with liver tissue, carried out using the developed techniques showed that with an increase in temperature the duration of preservation of analytes in biological material decreases. Moreover, the 2.4-isomer is more stable during storage than the 2.6-isomer. At temperatures of -25 °C, 0-2 °C, 8-10 °C, 20-22 °C, 36 °C the duration of retention of 2.4-dimethylhydroxybenzene is 402, 379, 358 and 224 days, respectively, the duration of retention of 2.6-dimethylhydroxybenzene is 356, 312, 224 and 136 days, respectively.

[Investigation of the distribution of (±)-N-methyl-3-phenyl-3-(para-trifluoromethyl) phenoxypropylamine hydrochloride in the body of warm-blooded animals]

THE AIM OF THE STUDY

Was to investigate the distribution of (±)-N-methyl-3-phenyl-3-(para-trifluoromethyl) phenoxypropylamine hydrochloride (fluoxetine) in the body of warm-blooded animals. For the experiments, Wistar rats were used. Fluoxetine was isolated from animal organs and bio-liquids by liquid-liquid extraction. Thin layer chromatography, UV spectrophotometry, and high performance liquid chromatography were used for identification and quantification. Techniques for isolating fluoxetine from urine, blood, intestinal contents, kidneys, and liver samples using liquid-liquid extraction are presented. Methods for identification and quantitative determination of fluoxetine in extracts by thin layer chromatography, UV spectrophotometry, and high performance liquid chromatography are described. The greatest amount of fluoxetine was found in the kidneys - 12.94±2.18 mg/100 g, the small intestine with contents - 9.50±1.90 mg/100 g and liver - 9.28±1.37 mg/100 g.

[Felodipine distribution in organisms of warm-blooded animals]

The objective of the work was to study felodipine distribution in warm-blooded animals (rats). The methods of TLC, GC-MS, and UV spectrophotometry were used in the experiments. A lethal dose of felodipine (1.05 g/kg) preliminary suspended in water was introduced intragastric into test animals (male rats of the Wistar line). The analyzed compound was isolated from solid tissues and blood of the animals with acetone, purified by the solvent replacement, and by macrocolumn chromatography with the Silasorb S-18 sorbent of 30 µm and polar eluent, acetonitrile-water (7:3). The analyte was identified by chromatographic behavior in a thin sorbent layer, retention time, and a set of positive ions in its mass spectrum, as well as by the UV spectrum. The analyte was quantitatively detected in biological matrices using UV spectrophotometry. The method was validated by the criteria of linearity, selectivity, accuracy, precision, limits of detection, and quantitative determination. The predominant content of felodipine was detected in tissues of the stomach (312.303±25.980 µg/g), small intestine with its contents (93.235±12.310 µg/g), stomach contents (80.072±8.510 µg/g), and in the spleen (26.083±1.758 µg/g).

[The specific features of the distribution of 2,4- and 2,6-di--butylhydroxybenzenes on the body of the warm-blooded animals]

The present study was designed to elucidate the character of the distribution of 2,4- and 2,6-di-tret-butylhydroxybenzenes (2,4-DTBHOB and 2,6-DTBHOB respectively) in the body of the warm-blooded animals (rats) following the administration of the three-fold LD₅₀ dose into the stomach. Both 2,4-DTBHOB and 2,6-DTBHOB were extracted from the blood and the organs of the perished animals by means of two-fold incubation of the sampled tissues in ethyl acetate with the subsequent purification of the isolates by passing the extracts through a L 40/100 mcm silicagel column using hexane:dioxane (8.5:1.5) for 2,4-DTBHOB and hexane:dioxane (97.5:2.5) for 2,6-DTBHOB as eluants. The compounds of interest were identified and quantified by means of TLC, HPLC, and UV-spectrometry. The study has shown that both 2,4-DTBHOB and 2,6-DTBHOB were present in the organs and blood of the poisoned animals in the unmetabolized form. Their largest amounts (mg/100 g) were found in the contents of the stomach, the small intestines with the contents and in the spleen.

[The peculiar features of the distribution of 2-metoxy-4-(1-propenyl)-hydroxybenzene in the organism of the warm-blooded animals]

The present study was designed to elucidate the distribution patterns of 2-metoxy-4-(1-propenyl)-hydroxybenzene in the organism of the warm-blooded animals (rats) after its intragastric administration at a dose equivalent to three 50% lethal doses (LD-50) for this compound. 2-metoxy-4-(1-propenyl)-hydroxybenzene was extracted in the unmodified form from the organs and blood of the dead animals after the dualfold infusion of the tissues with ethyl-acetate and purification by chromatography on a macrocolumn with silica gel L 40/100 mcm making use of the hexane-acetone mixture (7:3) mobile phase as the eluent. TLC, HPLC, and UV-spectrometry were employed to identify and quantify the analyte. The study has demonstrated the presence of unmetabolized 2-metoxy-4-(1-propenyl)-hydroxybenzene in the organs and blood of the poisoned animals. The largest amounts of this compound (expressed in milligrams per 100 g of the tissue) were accumulated in the stomach with its contents (236.22±28.21), small intestine with their contents (122.29±15.55), lungs (44.28±2.10), and spleen (44.00±4.70).