Polystyrene-block-polyglycidol micelles cross-linked with titanium tetraisopropoxide. laser light and small-angle X-ray scattering studies on their formation in solution.

Hybrid micelles from polystyrene-block-polyglycidol (PS-b-PG) copolymers with chemically cross-linked cores by titanium tetraisopropoxide (Ti(OC(3)H(7))(4)) were prepared in toluene solution. Additionally, micellization of PS-b-PG copolymers with different mass fractions of polyglycidol (x(PG)), was studied by static and dynamic light scattering as well as small-angle X-ray scattering. It was observed that copolymers with x(PG) smaller than 0.5 self-assembled in toluene into spherical core-shell micelles with hydrodynamic radii R(h) between 12 and 23 nm. On the other hand, copolymers with larger PG content formed particles with R(h) = 50-70 nm and aggregation numbers of several thousands. The presence of these aggregates in solution was attributed to the nonequilibrated form of block copolymers upon dissolving, most probably due to hydrogen bonding. In the following, spherical PS-b-PG micelles were loaded in toluene with hydrochloric acid and titanium tetraisopropoxide. Confined hydrolysis of Ti(OC(3)H(7))(4) induced by HCl in the micellar core was confirmed by small-angle X-ray scattering experiments. The subsequent condensation of the precursor with hydroxyl groups of polyglycidol chains led to covalently stabilized hybrid organic-inorganic particles. The presence of cross-linked PS-b-PG micelles was proven in two ways. First, micelles with "frozen" core showed stable hydrodynamic size in time upon dilution below critical micellization concentration while non-cross-linked PS-b-PG micelles underwent disintegration under the same conditions within several hours. Second, light scattering experiments revealed the presence of stable, swollen particles in N,N-dimethylformamide, which is a good solvent for both blocks.

Rapid preparation of flexible porous coordination polymer nanocrystals with accelerated guest adsorption kinetics.

Porous coordination polymers, in particular flexible porous coordination polymer networks that change their network structure on guest adsorption, have enormous potential in applications involving selective storage, separation and sensing. Despite the expected significant differences in their adsorption properties, porous coordination polymer nanocrystals remain largely unexplored, and there have been no reports about studies on flexible porous coordination polymer nanocrystals, mainly due to a lack of preparation methods. Here, we present a new technique for the rapid preparation of porous coordination polymer nanocrystals that combines non-aqueous inverse microemulsion with ultrasonication. Uniform nanocrystals of {[Zn(ip)(bpy)]}(n) (ip = isophthalate, bpy = 4,4'-bipyridyl; CID-1), a flexible porous coordination polymer, have been prepared by this method and analysed using field-emission scanning electron microscopy, energy-dispersive X-ray analysis, infrared spectroscopy, Raman spectroscopy and X-ray powder diffraction. A model for particle formation and growth is presented and discussed. Adsorption experiments with methanol show that the overall adsorption capacities of nanoparticles and bulk are almost identical, but the shapes of the sorption isotherms differ significantly and the adsorption kinetics increase dramatically.

[Investigation of local reaction of muscular tissue after injection of polyvinylpyrrolidone preparation]. / Badania miejscowej reakcji tkanki miesniowej po iniekcji preparatu poliwinylopirolidonu.

Natural preparations for replenishing of hyaluronic acid of zoogenous origin used till now, are characterized with quit low biocompatibility and also too short effect of their action. Recently worked out synthetic polyvinylpyrrolidone preparation PVP, contains modification constituting internally netting of microgels to improve polymer bioresistance. The introduce modification can, however influence PVP biocompatibility after deposition into tissues of the living organism. The aim of research was evaluation of the local reaction of muscular tissue after PVP infection. The results of research concerned a control group where normal saline was used for infections. The research was carried out on 18 Wistar rats and included macroscopic and histologic observations made in the 3rd, 5th, 7th, 14th and 30th day after PVP injection into thigh muscle. The local reaction of muscular tissue was macroscopically characterized with inflammatory reaction till the 7th day after PVP injection, in later terms the observed changes disappeared. Microscopic research showed that PVP till the 7th day after PVP injection caused rather strong diffuse non-specific inflammatory process, yet without essential participation of neutrophils leading to producing of loose intra-muscular. Connective tissue in a later term. The carried out tests showed presence of PVP in muscular tissue till the 30th day after injection.

[Tissue reaction after injection of polyvinylpyrrolidone (PVP) preparation into knee joint. Experiment]. / Odczyn tkankowy po iniekcji preparatu poliwinylopirolidonu (PVP) do stawu kolanowego. Badania doswiadczalne.

Internally netted miscogelatinated preparation on the basis of polyvinylpyrrolidone PVP desioned for viscosuplementation of joint fluid was worked out. Netted structure of microgel grains presents larger resistance to the degrading action of free radicals than analogical linear polymer chains. Application of zoogeous preparations of hyaluronic acid results in short-term effects of their usage in evoking reaction foreign protein. Replenishment of joint fluid with preparation with higher biostability from biocompatible synthetic polymer-polyvinylpyrrolidone could improve the function of synovial through restoration of its proper viscosity and protection of the joint for a longer period of time. The aim of the experiment was determination of bioresistance and reaction of microgel PVP on the tissues of synovial joint. The tests were carried out on 10 white New Zealand rabbits after injection PVP into the knee joint for 3, 7, 14 and 30 days and submitted to macroscopic and histological evaluation. The results of tests were compared with the data obtained after injection of normal saline. Macroscopically, there were no changes in the limits of articular capsule and cartilage; there was only slight and enlargement of synovial membrane in the first 7 days after PVP injection. In histological tests it was observed that reaction in the knee joint after PVP injection was characterised it single inflammatory chains without essential participation of neutrophils observed only in synovial membrane and limited to places were tested preparation was seen. Microgel PVP was present in diverticula of synovial membrane to 30th day after injection.