Anti-bacterial Properties of an in situ Forming Hydrogel Based on Oxidized Alginate and Gelatin Loaded with Gentamycin.

The release profiles and anti-bacterial properties of gentamycin (GEN) incorporated into in situ forming hydrogels for application as an in situ forming wound or burn dressing was investigated. Hydrogels were prepared by mixing gentamycin (GEN) with either a solution of the oxidized alginate in 0.1 M borax or a solution of gelatin in water and combining the two solutions. The release of GEN from these gels was studied by varying the order of mixing the drug with either oxidized alginate or gelatin. The antibacterial property of these gels was evaluated using gram negative P. aeruginosa and gram positive S. aureus. The gelation reaction between periodate-oxidized alginate and gelatin through Schiff's base formation was swift enabling in situ formation of GEN-loaded hydrogels. Drug release was slow when GEN was first mixed with oxidized alginate due to conjugation of the drug to the polymer through Schiff's base while release was more rapid when it was first mixed with gelatin. Drug payload also controlled the release of drug from the hydrogel matrix. Release occurred with an initial burst effect, followed by a relatively constant release. GEN released from the hydrogels was bactericidal against both strains of bacteria used for testing. [ABSTRACT FROM AUTHOR]