Arabic Gum Grafted PEGDMA Hydrogels: Synthesis, Physico-Chemical Characterization and In-vitro Release of Hydrophobic Drug

Abstract

Hydrogel development using natural and synthetic polymers for biomedical applications have shown promising properties for drug delivery due to virtuous stimuli response and improvement in mechanical strength. Biomaterial hydrogel was synthesized using combination of arabic gum (AG), a natural polymer and polyethylene glycol dimethacrylate (PEGDMA), a synthetic polymer. The synthesis process follows chemical cross linking by free radical polymerization. Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and differential scanning calorimetry (DSC) were used to characterize the hydrogels. Product yield, gel content and gelation time depends solely on the variable reacting concentrations and the mechanical properties of hydrogel depends on its compositions. Swelling studies reveal high swelling ratio in buffer solution pH 1.2 compare to buffer solution pH 7.4, and deionized water at pH 6.7. Swelling ratio raises with increase in PEGDMA concentration, but the presences of salt/ions solutions decreases the swelling ratio significantly and it depends on the charge of the ions. The kinetics of the swelling follows a second order non-linear rate equation. The rate of degradation revealed significant degradation in acidic medium and insignificant degradation was observed in basic medium. The encapsulation efficiency of quercetin introduced directly in the hydrogels during synthesis was found in the range of 85–94%. The release profile indicates the dependence of arabic gum grafted PEGDMA hydrogels on pH and compositions. The characteristic properties exhibited by the formulated hydrogels suggest the suitability of them to be applied as drug carriers.