Synthesis of starch-g-poly(acrylic acid-co-2-hydroxy ethyl methacrylate) as a potential pH-sensitive hydrogel-based drug delivery system

Authors : Mohammad SADEGHI

Pages : 723-733

Doi:10.3906/sag-1211-60

View : 15 | Download : 9

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :The present work focused on the design of a drug delivery system insert ignore into journalissuearticles values(DDS); based on pH-sensitive hydrogel. The hydrogels were prepared via graft copolymerization of mixtures of acrylic acid insert ignore into journalissuearticles values(AA); and 2-hydroxy ethyl methacrylate insert ignore into journalissuearticles values(HEMA); onto starch backbones by a free radical polymerization technique. Sodium bicarbonate insert ignore into journalissuearticles values(NaHCO3); was added to function as a foaming agent under acidic conditions, rendering the hydrogels to be porous. The porous structure of the hydrogel was essential in this system to yield a large surface area so that 5-fluorouracil insert ignore into journalissuearticles values(5-FU); release could be facilitated. The hydrogel, thus prepared, possessed a porous structure as determined by scanning electron microscopy. The water absorbency of the hydrogels was measured in solutions with pH levels ranging from 1 to 13. The starch-based hydrogel exhibited a pH-responsiveness character such that a swelling-deswelling pulsatile behavior was recorded at pH levels of 2 and 7. Using the drug 5-FU as a model molecule, the in vitro controlled drug-release behaviors of these hydrogels were investigated. The results indicate that the main parameter affecting the drug-release behavior of hydrogels is the pH of the solution. The release rate of 5-FU from hydrogel at pH 7.4 was faster than that at pH 1.2 due to the shrinkage of the hydrogel at pH 1.2. These results suggest that a porous hydrogel could potentially be a useful local delivery system to release drugs, primarily at a specific site of body.
Keywords : Starch, acrylic acid, 2 hydroxy ethyl methacrylate, hydrogel, drug delivery