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Information × Registration Number 0209U006076, 0106U003109 , R & D reports Title Control of interfacional processes and optimization of conditions in hybrid methods of chemical analysis popup.stage_title Head Loginova Lidiya Pavlovna, Registration Date 21-01-2009 Organization Kharkov national university named after V.N. Karazin popup.description2 The purpose of work: to synthesize new ormosils, hybrid organic mineral materials using sol-gel metod. To create theoretical bases and to develop physical-chemical models for control of processes on the interface between solution and surface of hybrid material (ormosil and stationare phases used in micellar liquid chromatography (MLC)). The purpose of the completing stage of the work: to create the means of the optimization of conditions of MLC, the new methods of separation and determination of organic components by MLC, recommendations for the choice of the optimal conditions of ormosil application in the analysis. Methods: spectrophotometry, spectroscopy of diffuse reflection, MLC, ionometry with dodecylsulfate selective electrode, scanning microscopy. Obtained results and novelty: new organo-mineral materials with immobilized analytical reagents-dyes Xylenol orange and calceine have been synthesized using sol-gel technology, which have advantage in comparison with solid-phase analytical reagents,making by sorption of dye on silica. The methods of control of the dye retention in ormosil matrice are found. The sorption and complex formation of metal ions on the ormosil surface are investigated, the distribution density of active centers is determined. It is found, the cooperative effects and the effects of energy heterogeneity considerably less influence on the sorption of metal ions, than in the case of silica gel with adsorbed dye. The peculiarity of stationary phases in MLC and hybrid micellar eluents is investigated. It is obtained in the firs time that the character of modification of surface of stationary phase С18 in MLC by micellar eluent component as well as surface properties change by temperature below phase translation of the bonded layer of the octadecyl radicals The new models of modification of surface of stationary phase С18 in MLC are developed. The set of new chemical and chemometrics tools for optimization of separation of analyte mixtures in MLC is created, which includes new heuristic retention model; reproducibility of retention factor data, that is an important for adequate modeling; complex of criterions, algorithm and program realization of optimization procedure; new effective modifiers of micellar mobile phases contained sodium dodecylsulfate. The chemometric approach is used for simultaneous optimization of separation in MLC in terms of selectivity, time of analysis and ruggedness. There ensure the rational design of preliminary experiments and reduce the search of acceptable conditions of separation by development of analytical methods with using MLC. The method of separation and quantification of 14 preservatives and related substances in food by minimal sample preparation is developed, studied, optimized and approved. The results of work can be used for improving of theory and modeling of separation in MLC, for control of separation processes in hybrid methods of analysis, for development and putting of new methods into practice of chemical analysis and quality control. Product Description popup.authors popup.nrat_date 2020-04-02 Close