Core-shell magnetosensitive nanocomposites (NC) based on single-domain magnetite (Fe 3 O 4 , core), with a shell consisting of hydroxyapatite (HA) and cytotoxic drug doxorubicin (DOX) layers have been synthesized. The processes of DOX adsorption on Fe 3 O 4 /HA surface from physiologic solution have been studied. DOX release into saline was found to decrease with growing of its quantity on NC surface. It has been determined that cytotoxic influence and antiproliferative activity of Fe 3 O 4 /HA/DOX NC with respect to Saccharomyces cerevisiae cells are characteristic for interaction of these cells with a free form of doxorubicin. Magnetic liquids containing Fe 3 O 4 /HA/ DOX NC stabilized by sodium oleate and polyethylene glycol were prepared and investigated. It is shown that using the ensemble of Fe 3 O 4 carriers as a superparamagnetic probe, the Langevin's paramagnetism theory, and the values of density of nanocomposite constituents, one can evaluate the size parameters of their shell, which has been corroborated by independent measurements of specific surface area of nanostructures and kinetic stability of the corresponding magnetic liquids. The obtained results may be useful for development and optimization of novel forms of magnetocarried medical remedies of targeted delivery and adsorbents based on nanocomposites of superparamagnetic core-shell type with multilevel nanoarchitecture, as well as for determination and control of the size parameters of its components.

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Наведено результати досліджень, спрямованих на розвиток концепції створення магніточутливих нанокомпозитів (НК) з багаторівневою ієрархічною наноархітектурою та функціями медико-біологічних нанороботів. Синтезовані нанорозмірний магнетит в однодоменному стані і магніточутливі НК на його основі (Fe 3 O 4 /дімеркаптосукцинова кислота (ДМСК), Fe 3 O 4 /γ-амінопропілсилоксан

The aim of the work is the synthesis and study of the bioactivity of sol-gel glass (BG 60S) with molar composition 60 % SiO2, 36 % CaO, 4 % P2O5 and samples doped with La and Y in vitro; studying their structural properties and changes upon contact with a model physiological environment (Kokubo’s SBF), as well as justifying the possibility of their use for tissue regeneration and tissue engineering. According to the results of research, the interaction of synthesized samples with SBF leads to a change in the phase composition and the ratio of amorphous and crystalline components. It is necessary to note long and intensive processes involving CO32– ions for unalloyed and alloyed samples. The appearance of calcium carbonate in the form of vaterite with a simultaneous increase in the calcite content is one of the signs of high bioactivity of the synthesized samples. According to the results of XRD, EDX and FTIR studies after 28 days of soaking in SBF, the predominant surface elements are Ca and P in the composition of hydroxyapatite, and the elemental composition indicates active ion exchange processes according to the theory of bioactive glass dissolution in physiological fluids. The change in the ratio of crystalline phases with the inclusion of mainly one crystalline phase of hydroxopatite within 28 days leads to a better structuredness of the surface of the synthesized samples and indicates that they have osteoconductive properties, can connect with bone tissue and have the appropriate biodegradation ability. The results of the study indicate the promising nature of synthesized materials for tissue regeneration and tissue engineering.

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The solvothermal method synthesized magnetite (Fe3O4) and investigated the processes of immobilization of the cytostatic drug doxorubicin (DOX) on its surface in the medium of 0.9% NaCl solution. The size and morphology (transmission electron microscopy (TEM), crystalline phase magnetite formation (X-ray diffraction analysis (XRD), FTIR spectroscopy) and magnetic properties (vibration magnetometer (VSM), specific surface area and pore size were determined by the method of nitrogen thermal desorption were investigated for the synthesized samples. The adsorption processes were studied and the high adsorption activity of the Fe3O4 nanoparticles (MNPs) surface with respect to DOX was established in the model physiological environment. According to the studies, the adsorption equilibrium time is 45-90 min with up to 80% DOX extraction and maximum adsorption capacity (Amax) 17.5 mg•g -1 . The analysis of kinetic dependences and DOX adsorption isotherms using mathematical models that take into account the chemical interaction in the system indicates the monomolecular nature of adsorption (Freundlich model).Obtained MNPs can be potentially suitable for oncology applications specifically in the targeted drug delivery and adsorption materials of intracorporeal and extracorporeal detoxification of the body.

The development of functional materials from food waste sources and minerals is currently of high importance. In the present work, polylactic acid (PLA)/silica composites were prepared by in situ ring-opening polymerizations of L-lactide onto the surface of pristine (Silochrom) and amine-functionalized (Silochrom-NH2) silica. The characteristics of the ring-opening polymerization onto the surface of modified and unmodified silica were identified and discussed. Fourier transform infrared spectroscopy was used to confirm the polymerization of lactide onto the silica surface, and thermogravimetric analysis determined that PLA constituted 5.9% and 7.5% of the composite mass for Silochrom/PLA and Silochrom-NH2/PLA, respectively. The sorption properties of the composites with respect to Pb(II), Co(II), and Cu(II) ions were investigated, and the effect of contact time, initial metal ion concentration, and initial pH were evaluated. Silochrom-NH2/PLA composites were found to have a higher adsorption capacity than Silochrom/PLA for all chosen ions, with the highest adsorption value occurring for Pb2+ at 1.5 mmol/g (90% removal efficiency). The composites showed the highest performance in the neutral or near-neutral pH (created by distilled water or buffer pH 6.86) during the first 15 min of phase contact. The equilibrium characteristics of adsorption were found to follow the Langmuir isotherm model rather than the Freundlich and Temkin models. Perspective applications for these PLA/silicas include remediation of industrial wastewater or leaching solutions from spent lead-acid and Li-ion batteries.

Наведено огляд наукових робіт, виконаних у минуле десятиліття, що стосуються розробок, дослідження властивостей, експлуатаційних параметрів, напрямів практичного використання магніточутливих наноматеріалів та нанокомпозитів, перспективних для створення нових форм комплексних лікарських препаратів з цитотоксичною, імунотерапевтичною і гіпертермічною дією, імуномагнітних сорбентів, засобів для деконтамінації вірусів з плазми і сироватки донорської крові людини тощо. Їх аналіз свідчить про актуальність окресленої тематики та перспективність застосування у різних галузях медицини, біології, біотехнології.