Opposite swelling characteristics through changing the connectivity in a biopolymeric hydrogel based on glycogen and glycine

Glycine, a biomolecule, has been functionalized through a simple condensation reaction with one of two functional groups (-COOH and -NH2) to prepare two vinylic monomers. On the other hand, glycogen has been methacrylated (Gly-Meth) to incorporate a polymerizable vinylic group. Finally, two different hydrogels, with reversible swelling characteristics, have successfully been synthesised through polymerization of each of these two monomers with Gly-Meth. The developed hydrogels with different connectivity demonstrate a superb pH responsive sustained release behaviour of model drugs (ciprofloxacin and naproxen).