Radiation Synthesis and Characterization of Drug Delivery System Based on Biopolymer Blends

Abstract

In this work preparation of blend based on poly(vinyl alcohol) (PVA) and different ratios (5 and 10 wt%) of methylcellulose (MC) were prepared into films by solution casting method using water as a common solventto form thin films,the PVA/MC blends were exposed to different doses ofgamma radiation.The blend was characterized in terms of gel fraction, swelling in water at room temperature and different pH values, IR spectroscopy, X-ray diffraction, structure morphology by scanning electron microscopy (SEM), thermal analysis by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC).The results showed decrease in swelling properties with increasing irradiation dose and (MC %),also the swelling % increase with pHvalue increase from pH 3 to pH 9. The effect of gamma irradiation on the thermal, and structure properties was investigatedof PVA/MC blends. The results showed increase in thermal stability with increasing irradiation dose due to the crosslinking between PVA/MC blend but, the stability slightly decrease with increasing MC %. The kinetic parameters such as energy of activation (Ea) and regression r2 for the thermal decomposition were determined by three different methods, the Coats-Redfern, Broido and Horowitz-Metzger methods were applied. The results indicated that the Ea and r2 values of the gamma irradiated PVA/MC blends as determined by the three methods were comparable.As an application in the field of the drug delivery system of gamma irradiated PVA/MC blends in the presence of drug, as an antibacterial antibiotic The blends before and after gamma irradiation were loaded with Doxycycline hyclate (DCH) as drug model and the chemical and physical properties was investigated in terms of gel content, swelling and surface morphology by scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The results show improved in all physical and thermalproperties which increased with adding (DCH). The gamma irradiated PVA/MC blends was evaluated for the possible use in drug delivery systems. In this respect, the release profiles of DCH from PVA/MC were investigated. It was found that the accumulated drug release from the blends increases with time to reach ~60% after 1 h at pH of 3 compared to ~100% at pH of 9. The results show effect of gamma radiationimproved all the physical properties, which provides suitable materials based on naturaland biodegradable polymers can be used as drug delivery materials.