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Information × Registration Number 0210U001469, 0107U000659 , R & D reports Title Quantitative relationships structure-retention-property of biological-active substances by micellar liquid chromatography data popup.stage_title Head Loginova Lidiya, Registration Date 17-02-2010 Organization Kharkov National University named after V.N. Karazin popup.description2 The purpose of work is to receive a set of the retention data of biologically active compounds in micellar liquid chromatography (MLC) and to construct the adequate multiparametric models for prediction of the biological activity of new compounds. Create a model for physical-chemical de-scription of interactions in microheterogeneous mobile phases used in modern hybrid methods of analysis. Methods: spectrophotometry, potentiometry, MLC, HPLC, quantum-chemical calculation, cluster analysis, principal component analysis, chemometrics, test analysis. Obtained results and novelty: A set of retention data of biologically active compounds (esters of 4-hydroxybenzoic acid, aromatic hydrocarbons and their hydroxy-, chloro-, nitro-derivatives, con-densed hydrocarbons, benzodiazepines, ?-blockers and others) was received by using MLC tech-nique. The possibilities and specific character of quantitative property-retention relationships model-ing in MLC have been investigated by using two approaches: the linear solvation energies relation-ships (LSER) and the quantitative structure-retention relationships (QSRR). LSER models, based on the use of physicochemical descriptors, are well describe the retention in MLC and permit to reveal the specific characteristics of chromatographic systems modified by alcohols or acids. An array of data on physical-chemical descriptors that are specific for MLC and biopartition chromatography, which describe the interactions in microheterogeneous mobile phases, was obtained. The ionization constants of several groups of substances in the micellar medium and the binding constants of ali-phatic carboxylic acids and esters of 4-hydroxybenzoic acids by micellar pseudophases of sodium dodecyl sulfate and Brij 35 were estimated. A new chemometric approach that ensures the effective reduction of initial descriptors array for construction of QSRR models, based on the use of calculated descriptors was propose. This ap-proach is based on the goal-directed selection of the most informative descriptors by using weighted incidence of their best correlations with experimental data. The chemometric method of optimization of the chromatographic separation, which has been proposed previously for MLC, was extended to widespread method of normal-phase TLC. It was found, that the best global criterion of separation is the product of discrimination factors of chroma-tographic spots. Adequacy of optimization and predictive power of models was confirmed by separa-tion of 7 food dyes. Giddins model was applied to simulate processes in micellar TLC for the first time. The effect of alcohols, modifying of the micellar eluent, on the the chromatographic time was accounted by decrease of surface tension of the mobile phase for the transition from ethanol to 1-pentanol.For the first time an approach for comparison of the chromatographic octadecyl silica columns (C18), produced by different trade mark, under MLC conditions has been developed. It allows to choose the chromatographic columns with similar separation selectivity. As follows from cluster analysis data, the individual properties of different trade mark columns are appeared to less extend in MLC mode than in the reversed-phase HPLC mode. The MLC method found to be more promising and versatile for construction of the quantitative structure-retention relationships and other physical-chemical investigations in comparison with the reversed-phase HPLC. New methods with the use of micellar mobile phases were developed for the separation of wa-ter- and fat-soluble vitamins and flavonoids in isocratic mode; for quantification of flavonoids in me-dicinal plant materials and preparations by using MLC method, for determination of impurity of 4-aminobutanoic acid in sodium alendronate substance by using micellar TLC. The time of analysis and consumption of toxic organic solvents are reduced significantly in comparison with conventional techniques. Product Description popup.authors Єдаменко Д. Бойченко О. Власенко Г. Дробот Д. Коновалова О. Левін І. Логінова Л. Нікітіна Н. Фролова А. Чернишова О. Шолом В. Яковлева О. popup.nrat_date 2020-04-02 Close