Design, characterization and evaluation of gelatin/carboxymethyl cellulose hydrogels for effective delivery of ciprofloxacin

The present work is to synthesize and characterize pH-sensitive gelatin/carboxymethyl cellulose (gelatin/CMC) hydrogels crosslinked with glutaraldehyde (GA). The effect of polymer ratio and crosslinking on dynamic swelling, equilibrium swelling and in vitro release pattern of model drug ciprofloxacin hydrochloride was investigated. Swelling and release studies were conducted in phosphate buffer solutions of various pH ranging from 1.2, 5.5 and 7.4. Hydrogels were characterized by FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM scanning electron microscopy and DSC (differential scanning calorimetry). The drug release data were fitted to various models to determine best fit release model. Drug-loaded hydrogels were further subjected to antioxidant, antibacterial and antifungal assays to assess the pharmacological profile of encapsulated drug, whereas cytotoxicity of prepared hydrogel was also evaluated. The results showed that maximum swelling and consequent highest release of drug occurred at pH 1.2 where gelatin was mainly responsible for swelling and release characteristics. The results of FTIR and XRD proved the crosslinking of polymers and compatibility of drug with polymers, whereas DSC confirmed the molecular dispersion of drug in the polymeric network. Release pattern of drug was zero order and the release of drug occurred through non-Fickian diffusion. The results obtained from various biological assays were sufficient to verify the hydrogels as potential drug carrier. Overall the results demonstrated the prepared hydrogels as a favourable drug carrier to achieve controlled drug release for different antimicrobial agents.