Design and evaluation of a bioadhesive patch for topical delivery of gentamicin sulphate.

The use of aminoglycoside antibiotics for the topical treatment of gram positive and gram negative infections especially bums and wounds has increased markedly in recent years. Patch formulation for topical delivery can be advantageously used as an alternative to conventional topical dosage forms. The present study aims to prepare and evaluate gentamicin sulphate patches for topical application and to study the effect of different bioadhesive polymers on diverse characteristics of prepared patches. Drug patches were evaluated for weight and thickness uniformity, moisture absorption capacity, tensile strength and percentage elongation. In vitro release patterns of these patches were studied and analyzed. Skin irritation and susceptibility testing of gentamicin sulphate formulae were also evaluated and compared to commercially available gentamicin sulphate cream. The thickness of the films was found to be uniform. Tensile strength of the patches prepared using HPMC as bioadhesive polymer was the lowest compared to the other patches. The in vitro release of the patches followed a pattern close to diffusion model. Patches formulated using HPMC gave the most superior results as compared to other compositions.