Preparation and in vitro evaluation of chitosan-based films for the sustained delivery of enrofloxacin

The implantable drug products are developed mainly to sustain the drug release. This study was conducted to formulate and evaluate cross-linked films of chitosan/β-glycerophosphate (β-GP) for the sustained delivery of enrofloxacin (ENR). Two types of formulations, single-layer (F1 and F2) and triple-layer (F3 and F4) films, were prepared. In vitro drug release, kinetic modelling, Fourier transform infrared spectroscopy (FTIR) spectra, morphological and microbiological studies were performed. Drug release from F1 and F2 continued up to 5 hours but from F3 and F4, it was extended over 96 and 168 hours, respectively. The cumulative drug release for F1, F2, F3 and F4 were 72.6, 70.1, 90.5 and 82.4%, respectively. The inhibition zones of bacterial growth by using positive controls and single layer films were significantly greater than those of triple-layer films (p < 0.05), indicating sustained drug release pattern of the multi-layer films. These findings suggest that the triple-layer chitosan/β-GP films could be effective to deliver ENR for a long period.