Biodegradable chitosan nanoparticle coatings on titanium for the delivery of BMP-2.

A simple method for the functionalization of a common implant material (Ti6Al4V) with biodegradable, drug loaded chitosan-tripolyphosphate (CS-TPP) nanoparticles is developed in order to enhance the osseointegration of endoprostheses after revision operations. The chitosan used has a tailored degree of acetylation which allows for a fast biodegradation by lysozyme. The degradability of chitosan is proven via viscometry.

Imidazolidene carboxylate bound MBPh4 complexes (M = Li, Na) and their relevance in transcarboxylation reactions.

Combination of 1,3-bis(2,6-diisopropylphenyl)imidazolum-2-carboxylate (IPrCO(2)) with the Lewis acids MBPh(4), where M = Li or Na, provided two separate complexes. The crystal structures of these complexes revealed that coordination to NaBPh(4) yielded a dimeric species, yet coordination of IPrCO(2) with LiBPh(4) yielded a monomeric species. Combination of 1,3-bis(2,4,6-trimethylphenyl)imidazolum-2-carboxylate (IMesCO(2)) with LiBPh(4) also afforded a dimeric species that was similar in global structure to that of the IPrCO(2)+NaBPh(4) dimer.