[The use of extractive freezing-out at the stage of preliminary preparation of bioprobes in GC-MS chemico-toxicological analysis]. / Primenenie ékstraktsionnogo vymorazhivaniia na étape predvaritel'noi podgotovki bioprob v GKh-MS khimiko- toksikologicheskom analize.

The authors propose a new express method of low-temperature sample preparation based on the use of extractive freezing-out combined with a sample centrifugation as a stage of a preliminary preparation of a biological object (cadaveric liver, kidneys). The method made it possible to minimize sufficiently the so-called chemical noise of endogenous coextractive substances and to improve sufficiently the conditions of the GC-MS method.

[The determination of pyrovaleron in the urine by gas chromatography in the combination with the method of extractive chilling-out and centrifugation]. / Gazokhromatograficheskoe opredelenie pirovalerona v moche metodom ékstraktsionnogo vymorazhivaniia v sochetanii s tsentrifugirovaniem.

The express-method for the determination of pyrovaleron in the urine based on the combination with the method of extractive freezing-out and centrifugation of the samples as the preliminary stage of the preparation of a biological object for the analysis. The identification and quantitative determination of the substance of interest were performed using gas chromatography with nitrogen-selective detection. The preparation of the samples was carried out as a single-step procedure no longer than 30 min in duration. The limit of alpha-pyrovaleron detection in the urine was estimated at 1 mcg/ml. Its concentration after extraction from the urine increased by a factor of more than nine.

[The isolation of organic compounds from hydrosulfuric mineral waters with the use of the extractive freezing-out technique with centrifugation]. / Vydelenie organicheskikh veshchestv iz serovodorodnykh mineral'nykh vod metodom ekstraktsionnogo vymorazhivaniya s tsentrifugirovaniem.

The mineral waters, enriched with organic substances find extensive application in balneotherapy. The fast and efficient methods for the identification and quantitative measurement of organic compounds (in the first place, organic acids) in such waters need to be developed for the estimation of their quality and biological activity. AIM: The objective of the present study was to elaborate a gas chromatographic method for the determination of monobasic carbonic acids in sulfide-containing mineral waters by means of extractive freezing-out in combination with the application of the centrifugal forces for the elucidation of the metrological characteristics of the compounds of interest. The secondary objective was to estimate the prospects for the application of the method of interest for determining the dissolved organic compounds in mineral waters. MATERIAL AND METHODS: The following carbonic acids were used for the purposes of the study: acetic acid (analytical grade), Russia; propionic grade (extra pure), Ferak, Germany; butyric acid (pure), Russia; valeric acid (pure), Russia; caproic acid (pure), Russia; oenanthic acid (pure), Russia; and caprylic acid (pure), Russia). Acetonitrile («O¼ grade), Russia, was used as the extracting agent. The LV-210 analytical balance (Russia) was used to prepare the model and standard solutions of the organic compounds and to determine their mass. The extracts and standard mixture were investigated by the gas chromatographic technique with the use of the Kristallyuks apparatus («Meta-Khrom¼, Russia) equipped with the flame ionization detector and the capillary column. Extractive freezing-out in the combination with centrifugation was performed with the laboratory installation for this purpose. RESULTS: Under the model conditions, a single extractive freezing-out procedure with the centrifugation of the sample made it possible to reach the 22-37-fold concentration of C2-C8 monobasic carbonic acids during their transfer from water into acetonitrile. The metrological parameters of the proposed procedure for gas-chromatographic determination of the aforementioned acids in hydrosulfuric mineral waters were estimated. The limit of detection of acetic and propionic acids has been 0,2 mg/l, that for butyric acid 0,1 mg/l, for valeric, caproic, oenanthic and caprylic acids 0,05 mg/l. We failed to identify C2-C8 carbonic acids in hydrosulfuric water from the 6T well of the field Matsesta fields. The investigation of the extracts obtained by the proposed extraction procedure with the use of the newly developed variant of high performance liquid chromatography (HPLC) with diode-matrix detection revealed the presence of various amounts of unknown organic substances. The UV-spectrum of one of those components was obtained which made it possible to conjecture its molecular structure. The procedure for the sample preparation and the following determination of organic acids in water is simple, carried out in a single stage, and does not impose special requirements to the qualification of the researcher. It allows to describe the newly developed technique as a rapid test method. Along with it, realization of extraction in the negative temperature mode reduces the risk of decomposition of the thermally unstable chemical compounds being extracted and reduces volatility of the organic solvents being used. The technology of the method does not demand a special laboratory glassware and expendables.

[The application of climatic therapy in the health resorts of the Black Sea coast of the Caucasus: the current state-of-the-art and the prospects for the further development]. / Klimatoterapiya na kurortakh Chernomorskogo poberezh'ya Kavkaza: sovremennoe sostoyanie i perspektivy razvitiya.

UNLABELLED: The present review summarizes the data published in the domestic and foreign literature concerning the history of climatic therapy, the current concepts of the mechanisms of action of the climatic and weather factors on the human body, the modern therapeutic modalities and technologies for health promotion. We consider not only the achievements but also the problems arising from insufficient knowledge of the impacts of current climate and extreme weather conditions on the state of human health and some disputable issues of the new methods and technologies of climatic therapy. IN CONCLUSION: the promising areas of further research and developments pertaining to climatic therapy as practiced under conditions of the Black Sea coast resorts.

[Rapid detection of caffeine in blood by freeze-out extraction].

A new method for the detection of caffeine in blood has been proposed based on the combination of extraction and freezing-out to eliminate the influence of sample matrix. Metrological characteristics of the method are presented. Selectivity of detection is achieved by optimal conditions of analysis by high performance liquid chromatography. The method is technically simple and cost-efficient, it ensures rapid performance of the studies.

[Methods of vapour-phase extraction and extractive freezing for the analysis of organic substances dissolved in mineral waters of the Sochi spa area].

The chromatomass-spectrometry method was for the first time employed to study organic substances isolated by vapour-phase extraction from the Matseta sulfide-containing mineral water near Sochi. These substances are found to contain sulphur in different valent forms. A new technique has been developed for the detection of monobasic C2-C6 carboxylic acids in natural mineral water based on the combination of sequential vapour extraction and extractive freezing of the analytes. The proposed method is readily reproducible and has a detection limit of 0.03 mg/l for the analysis of carboxylic acids in water.

[Application of extraction freezing for analysis of 1,4-benzodiazepines in urine].

A test for 1,4-benzodiazepines in urine is described. Extraction and freezing were used at the stage of the sample preparation. Metrological characteristics of the method are presented. Selectivity of the test is provided by optimal conditions for high-performance liquid chromatography. The technique is simple to use and cost-effective.