Deswelling of Hydrogels in Aqueous and Polyethylene Glycol Solutions. A New Approach for Drug Delivery Application
To enhance the properties of pure poly(acrylamide) hydrogel, diprotic maleic acid co-monomer was included into the reaction mixture during hydrogel synthesis. These hydrogels have been shown important swelling in distilled water and deswelling in acidic solution. In present work, we based on these considerations to study the deswelling behaviour of poly(acrylamide-co-maleic acid) hydrogels in different media (air, polyethylene glycol 200 (PEG200), acidic solution). Hydrogels of poly(acrylamide) and its copolymers with maleic acid were prepared by copolymerization and chemical crosslinking with methylene bisacrylamide. The obtained hydrogels have shown substantial mass swelling in distilled water and shrinking in acidic solution and PEG200. Results showed that the PEG200 was a better solvent for hydrogel deswelling and possibly will be used for gel drying.
The swelling and deswelling kinetics were described by second-ordered and first-ordered models, respectively. BSA desorption in PEG200 was also studied.