Mechanochemistry and solubilization of drugs

The results on solubilization of poorly water-soluble drugs, indomethacin, piroxicam, and meloxicam, with the help of mechanochemical methods are presented. The mechanocomposites of the drugs with various excipients, including soluble polymers and non-soluble fine porous inorganic oxides, were obtained by co-grinding using vibrational and planetary centrifugal mills. The samples obtained revealed higher release rate and apparent solubility of the drugs with respect to the initial ones. Nevertheless, in some cases, e.g. for composites of piroxicam with alumina and ferric oxide, decreasing the release rate and solubility of the drug was observed suggesting the formation of poorly soluble strong drug - carrier associates

Radiation-Thermal Synthesis of Copolymers of Chitosan with Acrylamide as a Means of Betulin Delivering

Радиационно-термическим методом с использованием ускоренных электронов получены привитые сополимеры хитозана с акриламидом. Образование привитых сополимеров подтверждено методами ИК‑спектроскопии и гель-проникающей хроматографии. Показано, что эффективность и степень прививки зависят от дозы ионизирующего облучения и с ростом дозы проходят через максимум. Найдены условия получения сополимеров с высоким выходом продукта. Полученные сополимеры использованы для получения композитов бетулина с помощью механохимической обработки. Показано, что скорость выделения бетулина в водный раствор при растворении композита зависит от pH раствора, что позволяет рассматривать механокомпозиты на основе сополимеров хитозана с акриламидом как перспективные средства для контролируемой доставки лекарственных веществGraft copolymers of chitosan with acrylamide were obtained by the radiation-thermal method using accelerated electrons. The formation of graft copolymers was confirmed by IR spectroscopy and gel permeation chromatography. It is shown that the efficiency and degree of grafting depend on the dose of ionizing radiation, and pass through a maximum with increasing dose. The conditions for obtaining copolymers with a high yield of the product were found. The resulting copolymers were used to obtain betulin composites using mechanochemical processing. It has been shown that the rate of release of betulin into an aqueous solution during the dissolution of the composite depends on the pH of the solution, which makes it possible to consider mechanocomposites based on copolymers of chitosan with acrylamide as promising means for controlled drug deliver

Effect of ball-milling on the formation of betulin and betulin diacetate composites with polyethylene glycol

Betulin and betulin diacetate (BDA) composites with polyethylene glycol (PEG) were obtained by ball-milling. In case of betulin - PEG mixtures, there was almost complete amorphization under ball-milling. On the contrary, there were no significant changes in the intensity of the reflections in the powder X-ray diffraction patterns for ball-milled mixtures of BDA with PEG. Dissolution of BDA in PEG melts formed at the contacts of particles under collisions with milling bodies leading to crystallization of the drug was suggested. An opportunity to dissolve BDA crystals in PEG melt followed by their crystallization was proven by DSC and hot stage optical microscopic observatio

Effect of the Selected Inorganic Carriers on the Properties of Mechanocomposites with Drugs

Hybrid core–shell type composites, including organicinorganic composites, possess unique proper ties and, hence, find use in many areas of science and technology, in particular, in pharmacy [1]. Mecha nochemical methods are efficient for the preparation of such materials because they shorten the duration of synthesis and avoid using large amounts of organic sol vents [2]. Rather popular inorganic drug carriers are highly porous alumina, silica, and magnesia [3, 4]. Hydroxides, which are mechanically softer and, due to layered structure, can be more easily mechanically activated are even more promising for the use in pharmacy

Влияние микроволнового облучения на арабиногалактан и его взаимодействие с диацетатом бетулина

Текст статьи не публикуется в открытом доступе в соответствии с политикой журнала.Betulin diacetate (BDA) has a variety of biological activities, but poor solubility in water limits its application. The use of arabinogalactan (AG) as a complexing agent is a promising method for solving the problem of solubilization of drugs. In this study, effect of microwave (MW) irradiation on the properties of AG and BDA and their interaction in aqueous suspension with the formation of a water-soluble supramolecular complex was studied. It is shown that the microwave heating of AG under harsh conditions can lead to degradation of the biopolymer. The use of microwave heating could significantly reduce the complex preparation time compared to the conventional synthesis in a water bath. The preliminary mechanical treatment of the mixture of components, leading to the formation of mechanocomposites, inhibited the reaction between the components in the aqueous suspension under microwave irradiation. The IR spectroscopy method has shown that a supramolecular complex formed under microwave irradiation similar to that formed by conventional heating. The BDA-AG complex was isolated from a microwave heated solution as a thin film, which may be a promising material for pharmaceutical applications

New composites of betulin esters with arabinogalactan as highly potent anti-cancer agents

Betulin and its esters are the natural compounds with high in vitro cytotoxicity toward many cancer cells. However, the poor water solubility of these compounds has limited their applications. We prepared new composites of betulin esters using two methods, namely ball milling of the mixtures of betulin esters with arabinogalactan and preparation of thin films of these mixtures by evaporating the aqueous solutions. These composites revealed higher water solubility as compared to the initial substances without losing the structural integrity and functionality of these compounds. As a result, the new composites have shown much higher inhibitory effects against different cancer cell lines such as Ehrlich ascite carcinoma cells and lung carcinoma cells (A549) in comparison with the initial substances. The cell viability studies based on Annexin V and Propidium iodide probes have confirmed the high proapoptotic effect of betulin esters derivatives against cancer cells

New composites of betulin esters with arabinogalactan as highly potent anti-cancer agents

Betulin and its esters are the natural compounds with high in vitro cytotoxicity toward many cancer cells. However, the poor water solubility of these compounds has limited their applications. We prepared new composites of betulin esters using two methods, namely ball milling of the mixtures of betulin esters with arabinogalactan and preparation of thin films of these mixtures by evaporating the aqueous solutions. These composites revealed higher water solubility as compared to the initial substances without losing the structural integrity and functionality of these compounds. As a result, the new composites have shown much higher inhibitory effects against different cancer cell lines such as Ehrlich ascite carcinoma cells and lung carcinoma cells (A549) in comparison with the initial substances. The cell viability studies based on Annexin V and Propidium iodide probes have confirmed the high proapoptotic effect of betulin esters derivatives against cancer cells