Polysaccharide and protein based microparticles for ophthalmic formulations

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Hydrogels based on carboxymethylcellulose and gelatin for inclusion and release of chloramphenicol

cited By 15International audienceHydrogels based on carboxymethylcellulose (CMC) and gelatin (GEL) crosslinked with glutaraldehyde were used to obtain interpenetrated- interconnecting polymer networks. They are designed to obtain controlled release polymeric drug systems. CMC and GEL were chosen for their biocompatibility and nontoxicity, which are compulsory conditions for polymers used in biomedical applications. By modifying the parameters of the crosslinking reaction, the obtained networks presented different crosslinking degrees and hence different swelling capacities. These properties determined the quantity of drug able to be loaded (0.25 g per gram of hydrogel). We obtained systems for which biologically active matter release was controlled by diffusion. The kinetics were zero-order during the major part of release period (∼500 min). These systems improve the bactericide activity compared with free drugs

Hydrogels based on carboxymethylcellulose and poly (vinyl alcohol) for controlled loading and release of chloramphenicol

cited By 8International audienceHydrogels based on carboxymethylcellulose (CMC) and poly (vinyl alcohol) (PVA), crosslinked with epichlorohydrine in basic medium, are polymeric materials interpenetrated network type, designed for development of polymer-drug systems with sustained release. CMC and PVA are polymers (natural, respectively synthetic) characterized by biocompatibility and biodegradability, important conditions for the polymers used for medical applications. The preparation of this new type of hydrogels is aimed to obtain a new type of macromolecular supports able to include and release in a sustained way hydrosoluble drugs (chloramphenicol). By the variation of the crosslinking reaction parameters there were developed networks with different crosslinking degrees, respectively with different swelling degrees, which influence the drug loading degree. For obtaining diffusional systems, the hydrogels with maximum swelling degree, characterized, a priori, by zero order release kinetics, were selected. The same systems were characterized from the point of view of antimicrobial activity by microbiological tests

Hydrogels based on carboxymethylcellulose and poly (vinyl alcohol) for controlled loading and release of chloramphenicol

cited By 8International audienceHydrogels based on carboxymethylcellulose (CMC) and poly (vinyl alcohol) (PVA), crosslinked with epichlorohydrine in basic medium, are polymeric materials interpenetrated network type, designed for development of polymer-drug systems with sustained release. CMC and PVA are polymers (natural, respectively synthetic) characterized by biocompatibility and biodegradability, important conditions for the polymers used for medical applications. The preparation of this new type of hydrogels is aimed to obtain a new type of macromolecular supports able to include and release in a sustained way hydrosoluble drugs (chloramphenicol). By the variation of the crosslinking reaction parameters there were developed networks with different crosslinking degrees, respectively with different swelling degrees, which influence the drug loading degree. For obtaining diffusional systems, the hydrogels with maximum swelling degree, characterized, a priori, by zero order release kinetics, were selected. The same systems were characterized from the point of view of antimicrobial activity by microbiological tests

Controlled release of water soluble antibiotics by carboxymethylcellulose- And gelatin-based hydrogels crosslinked with epichlorohydrin

cited By 13International audienceHydrogels based on carboxymethylcellulose (CMC) and gelatin (GEL) crosslinked with epichlorohydrin in alkaline environment are polymeric interpenelrated-interconnected network materials, designed for obtaining controlled release polymer-drug systems. CMC and GEL are chosen due to their biocompatibility and non-toxicity - compulsory conditions for the polymers used in biomedical applications. By modifying the parameters of the crosslinking reaction, the obtained networks present different crosslinking degrees and hence different swelling capacities, properties determining the quantity of the drug to be included. Hydrogels with the highest swelling degree were loaded with water soluble drugs (chloramphenicol - sodium hemisuccinate, CIPh). We have thus obtained systems with diffusioncontrolled release, with zero-order kinetics during most of the release period. These systems prove a high bactericide activity, comparable to that of free drugs

Double Cross-linked Chitosan—Gelatin Particulate Systems for Ophthalmic Applications

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