Synthesis of a novel biodegradable gelatin-based drug delivery system

A drug delivery system is defined as an interface between the patient and the drug and varies according to the anatomical route (oral, inhalation, transdermal, etc.), the formulation (capsules, gels, combination with liposomes, etc.) or the device used (pumps, delivery conduits, reservoirs, etc.). The focus of research efforts in the drug delivery field has been on developing delivery systems that can deliver drug at a predictable release rate independent of their environment. Biodegradable natural-based polymers have received significant attention in recent years due to their exceptional promise for pharmaceutical and medical applications. Superabsorbent polymers are special soft and pliable polymeric materials that can be absorb large quantities of water, saline or physiological solutions while the absorbed solutions are not removable even under pressure [1,2]. Because of their superior properties, they have found extensive applications such as disposable diapers, feminine napkins, drug delivery systems [3,4]. The synthesized hydrogels in this work from pH-sensitive gelatin-g-poly(acrylic acid) were subjected to equilibrium swelling studies in simulated gastric and intestinal fluids (SGF and SIF). Hydrogels containing drug diclofenac sodium (DS) at different drug-to-polymer ratios were prepared by direct adsorption method. The loading yield was found to depend on both the impregnation time and the amount of encapsulated drug. In vitro drug-release studies in different buffer solutions showed that the most important parameter affecting the drug-release behavior of hydrogels is the pH of the solution.