Studi di preformulazione di sistemi a rilascio sito-specifico e prolungato di vancomicina e teicoplanina

Also CRG revealed a suitable carrier for prolonging drug release with a marked retarding effect from drug-carrier physical mixtures. Gelification of CRG in contact with the dissolution media can be assumed to be responsible for the slowing down effect on drugs release due to the diffusion through the gel. The presence of TAgammaCd as a ternary component does not play a significant role in this respect. IDR values for stored VCM?HCl-TACd and TCP-TACd systems showed the best performance of the drug-TAgammaCd physical mixtures 1:3 drug-to-carrier mass ratio (10 times and 28 times reduction of IDR of VCM?HCl alone and TCP alone, respectively). Comparing IDR values of stored and freshly prepared drug-TACd binary systems, no significant differences in the drug release profiles for VCM?HCl after storage were found, whereas TCP-TACd combinations showed an increase in the IDR values after storage, except the TCP-TAbetaCd coevaporated system in the 1:1 drug-to-carrier mass ratio whose IDR value decrease from 0,826 mg cm-2 min-1 (freshly prepared system) to 0,631 mg cm-2 min-1 (stored system). The systems in the drug-to-carrier 1:1 (by weight) ratio (approximately 1:1 (mol/mol) ratio) which can be proposed for further studies on antibiotate PMMA cements, on the basis of the capacity of slowing down the in vitro drug release, are: (a) for VCM?HCl with TAalfaCd: kneading product (0,229 mg cm-2 min-1); with TAbetaCd: physical mixture (0,204 mg cm-2 min-1); with TAgammaCd: physical mixture (0,174 mg cm-2 min-1) (b) for TCP with TAalfaCd: kneadi