Некоторые особенности структурной динамики межсекторальных ресурсных потоков в научной системе Украины

Представлен анализ динамики финансирования научно-технической деятельности в аспекте основных источников средств и исполнителей за весь период независимости Украины. Изложен авторский подход к оцениванию роли государства и других экономических субъектов, который адаптирует требования международных учетных стандартов к реалиям отечественной экономики.Представлено аналіз динаміки фінансування науково-технічної діяльності в аспекті головних джерел коштів та виконавців за весь період незалежності України. Викладено авторський підхід до оцінювання ролі держави та інших економічних суб’єктів, що адаптує вимоги міжнародних облікових стандартів до реалій вітчизняної економіки.An analysis of the R&D funding dynamics in terms of main funding sources and performers over the period of the Ukrainian independence is given. The author’s approach to evaluating the role of the government and other economic entities, which adapts the requirements of international accounting standards to the realities of the national economy, is shown

A Kinetic Degradation Study of Curcumin in Its Free Form and Loaded in Polymeric Micelles

Curcumin, a phenolic compound, possesses many pharmacological activities and is under clinical evaluation to treat different diseases. However, conflicting data about its stability have been reported. In this study, the kinetic degradation of curcumin from a natural curcuminoid mixture under various conditions (pH, temperature, and dielectric constant of the medium) was investigated. Moreover, the degradation of pure curcumin at some selected conditions was also determined. To fully solubilize curcumin and to prevent precipitation of curcumin that occurs when low concentrations of co–solvent are present, a 50:50 (v/v) aqueous buffer/methanol mixture was used as standard medium to study its degradation kinetics. The results showed that degradation of curcumin both as pure compound and present in the curcuminoid mixture followed first order kinetic reaction. It was further shown that an increasing pH, temperature, and dielectric constant of the medium resulted in an increase in the degradation rate. Curcumin showed rapid degradation due to autoxidation in aqueous buffer pH = 8.0 with a rate constant of 280 × 10-3h-1, corresponding with a half–life (t1/2) of 2.5 h. Dioxygenated bicyclopentadione was identified as the final degradation product. Importantly, curcumin loaded as curcuminoid mixture in ω–methoxy poly (ethylene glycol)–b–(N–(2–benzoyloxypropyl) methacrylamide) (mPEG–HPMA–Bz) polymeric micelles and in Triton X–100 micelles was about 300–500 times more stable than in aqueous buffer. Therefore, loading of curcumin into polymeric micelles is a promising approach to stabilize this compound and develop formulations suitable for further pharmaceutical and clinical studies

Micellar electrokinetic chromatography-electrospray ionization mass spectrometry employing a volatile surfactant for the analysis of amino acids in human urine

A new MEKC-ESI-MS method for the analysis of amino acids (AAs) in human urine was developed employing ammonium perfluorooctanoate (APFO) as volatile surfactant. The influence of APFO on the MS signal of AAs was evaluated by infusion experiments, which showed that APFO hardly affects analyte responses and presents significantly less ion suppression than equal concentrations of ammonium acetate. In order to obtain efficient separation of AAs, MEKC parameters such as the pH and APFO concentration of the BGE, were optimized. Optimum AA resolution, including baseline separation of leucine and isoleucine, was obtained using 150 mM APFO (pH 9.0) as BGE, representing a considerable selectivity improvement over CE using 50 mM ammonium acetate (pH 9.0). Optimization of CE-MS parameters, such as sheath liquid composition and flow rate, and ESI and MS settings, led to LODs ranging from 9 to 26 ng/mL for the 20 tested AAs, which is highly favorable for an MEKC-MS method. Good linearity (