In situ Crosslinking System of Gelatin with Acrylated β-cyclodextrin Towards the Fabrication of Hydrogels for Sustained Drug Release

Abstract

Cyclodextrins (CDs) are of interest in the fabrication of various polymeric platforms, especiallythe crosslinked networks that possess unique advantages in biomedical applications. When one benefitsfrom the abilities of CDs to form inclusion complexes with hydrophobic drug molecules, hydrogel-basedsupported drug platforms employ CDs as nano-buckets in the network structure. In the current study, wereport on the fabrication of gelatin-based hydrogels chemically crosslinked with acrylated β-cyclodextrin (βCD) as sustained drug release platforms. A practical and straightforward synthesis of crosslinked networkswas achieved by Michael's addition reaction of gelatin amino functionalities onto acryloyl groups of modifiedβ-CD. Tunable synthesis of hydrogels incorporating a different amount of β-CD molecules was maintainedby simple adjustment of the reaction stoichiometry between amine and acrylate groups. The resultinghydrogels were characterized by their surface morphology, equilibrium swelling ratios, and rheologicalproperties. Thus obtained hydrogels were evaluated in terms of their drug loading capacities and sustainedrelease efficiencies. The results demonstrated that the amount of drug loading and prolonged release isdependent on the amount of β-CD in the gel network. Thanks to their in situ gel-forming abilities, thesehydrogels can be used as injectable formulations for various biomedical applications.