Radiation Synthesis of Functionalized Gum Arabic and Hydroxyethyl Methacrylate Hydrogels for the Controlled Release of Niacin (Vitamin B3)

For modern drug delivery, we need not only to develop new hydrogels but also appropriate processing approaches for them. Polysaccharides are potential competitors since they can be chemically modifiable, prepared prior to crosslinking, and yielded into hydrogels with a given form and shape. In this study, we performed chemical modification of gum arabic (GA) by amination reaction followed by conjugation with niacin (vitamin B₃). Copolymeric hydrogels were developed by irradiating the mixtures of aqueous solutions of niacin conjugated aminated gum arabic (N–AmGA) and 2-hydroxyethyl methacrylate (HEMA) (0/100, 20/80, 30/70, and 40/60 wt%) via gamma irradiation technique at different doses 10, 15, 20 and 25 kGy at a dose rate of 02.681 kGy/h for sustained and prolonged delivery of niacin. Effect of copolymer composition and an irradiation dose on gelation was examined to evaluate the optimum conditions for stable hydrogel fabrication. The copolymeric hydrogels exhibit unique characteristics in terms of mechanical properties, porosity, pH, temperature, responsive behavior, and niacin release. In-vitro release of niacin from the hydrogels at different pH (water of pH 7.0, simulated intestinal fluid of pH 4.5 and simulated gastric fluid of pH 1.5) was also investigated. The water absorption and in vitro niacin release was observed to be higher at higher pH. Different kinetic models were applied to check the best fit for the niacin release mechanism. The results revealed that the kinetics data of the niacin release shows the best fit with the Korsmeyer–Peppas model due to its coefficient of correlation close to unity. Therefore, in this study, a new approach was successfully suggested for the preparation of N–AmGA/HEMA copolymeric hydrogel with controllable and prolonged release of niacin for possible application in vitamin deficiency disorders.