Gum kondagogu-g-poly (acrylamide): Microwave-assisted synthesis, characterisation and release behaviour

Microwave-assisted grafting of gum kondagogu onto poly (acrylamide) was carried out employing two-level, four-factor full factorial experimental design. Gum kondagogu-g-poly(acrylamide) was characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray diffraction and scanning electron microscopy. Microwave power, microwave exposure time and the concentration of ammonium persulfate had significant synergistic effect on grafting efficiency, while the concentration of gum kondagogu had no significant effect. The optimal calculated parameters were microwave power-40%, microwave exposure time-120 s, concentration of ammonium persulfate-10 mmol and concentration of gum kondagogu 3% (w/v). Comparative evaluation of the in vitro release of diclofenac sodium from the matrix tablets of gum kondagogu and gum kondagogu-g-poly(acrylamide) revealed a faster release of drug from gum kondagogu-g-poly(acrylamide). Further, the matrix tablets of gum kondagogu and commercial tablets were found to release the drug by zero-order kinetics, while the gum kondagogu-g-poly(acrylamide) matrices released the drug by Higuchi square-root kinetics.