Citric Acid Crosslinked Hydrogel Dressings for Delivery of Metronidazole

The objective of this study was to synthesize and characterize citric acid crosslinked hydrogel films of carboxymethyl tamarind gum for topical drug delivery system. The hydrogel films were characterized by attenuated total reflectance- Fourier- transform infrared spectroscopy, solid state 13C- nuclear magnetic resonance spectroscopy and differential scanning calorimeter. The prepared hydrogel films were evaluated for the carboxyl content and equilibrium swelling ratio. Metronidazole was loaded into these hydrogel films and drug release was monitored in different PH medium. Hemolysis assay was used to study Biocompatibility of hydrogel films. Results of attenuated total reflectance- Fourier- transform infrared spectroscopy solid state 13C- nuclear magnetic resonance spectroscopy and differential scanning calorimeter confirmed the formation of citric acid crosslinked hydrogel films. Total carboxyl content of hydrogel film was found to be increased when polymer ratio and amount of citric acid was increased. On the other hand swelling of hydrogel film was found to be decreased with increase in polymer ratio and amount of citric acid. Results of haemolysis assay indicated that the citric acid crosslinked hydrogels were safe to be used in drug delivery. In vivo wound healing study showed that metronidazole loaded hydrogel film has significant higher wound healing rate than control group, group 1, and group 3. This indicated that prepared hydrogel films can be successfully used as dressings for wound healing.