RESUMO
Hyaluronan (HA) films exhibit properties suitable for medical applications, but the solubility of HA limits their use in aqueous environments. This can be overcome by modifying HA with hydrophobic side groups that enable physical cross-linking. In this work, we present water insoluble free-standing films from lauroyl modified HA as novel biomaterials with properties tuneable by the degree of HA substitution. The films are homogeneous, mechanically strong, and flexible and can be sterilized by ethylenoxide. To characterize the films, we measured their thickness, dry mass, content of residual organic solvent, mechanical properties, swelling and enzymatic degradation. The safety and biodegradability of the films were tested both in-vitro and in-vivo, showing that the films are safe and that their degradation can be tailored by the degree of HA substitution.
Assuntos
Materiais Biocompatíveis/química , Ácido Hialurônico/química , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/metabolismo , Ácido Hialurônico/efeitos adversos , Ácido Hialurônico/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Masculino , Fenômenos Mecânicos , Camundongos , Camundongos Endogâmicos C57BL , Segurança , SolubilidadeRESUMO
The present paper deals with the preparation and characterization of a conjugate of isoniazid (INH) with the block copolymer methoxypoly(ethylene glycol)-b-poly(L-lysine) (mPEG-b-PLL). The structure of the conjugate (mPEG-b-PLL-INH) was verified by means of (1)H NMR, GPC, infrared spectroscopy, elemental analysis and powder X-ray diffraction. The conjugate contains six l-lysine units with five INH molecules, which are attached by means of pH-sensitive amidine bond. Under in vitro conditions, the conjugate is hydrolyzed and isoniazid is released (pH 4; 37 °C; t(1/2) ≈ 10 h).