Chitosan coatings with enhanced biostability in vivo.

In this article, we study the stability of chitosan coatings applied on glutaraldehyde-stabilized bovine pericardium when exposed to biodegradation in vivo in the course of model subcutaneous tests on rats. The coatings were deposited from carbonic acid solutions, that is, H O saturated with CO at high pressure. Histological sections of treated pericardium samples demonstrated that the structure of pericardial connective tissues was not significantly altered by the coating application method.

Formation of Easy-to-Recover Polystyrene--Poly(4-vinylpyridine) Micelles Decorated with Pd Nanoparticles in Solutions of Self-Neutralizing Carbonic Acid.

It was found out that block copolymers of polystyrene and poly(4-vinylpyridine) with comparable lengths of blocks could be dissolved in a high-pressure reactor containing water phase saturated with carbon dioxide under high pressure at room temperature. This rather effective dissolution occurs due to a protonation of P4VP nitrogen-containing groups together with a plasticization of the polymer material to be dissolved by a compressed dense CO being contained in the autoclave. The selected block copolymers form rather monodispersed micelles with well-defined and reproducible spherical geometry.