Hydrogels Based on Carboxymethylcellulose and Gelatin for Inclusion and Release of Chloramphenicol

Hydrogels 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.