Inulin vinyl sulfone derivative cross-linked with bis-amino PEG: new materials for biomedical applications

In this work new hydrogels based on biocompatible polymers such as inulin (INU) and O,O'-bis(2-aminoethyl)polyethyleneglycol (PEGBa) have been prepared and charaterized. In particular, INU has been derivatized with divinyl sulfone (DV) thus obtaining the INUDV derivative, a copolymer bearing double bonds highly reactive towards the conjugate addition by nucleophilic molecules. INUDV has been characterized by FT-IR, 1H-NMR and SEC analyses that have confirmed the success of the derivatization reaction. With the aim to obtain novel hydrogel systems, INUDV derivative has been cross-linked with PEGBa in phosphate buffer solution pH 7.4. The reaction has been carried out for 4 h at room temperature and various samples have been obtained by changing the amount of PEGBa. These hydrogels resulted to be homogeneous, transparent, colorless and odorless and they have been characterized by spectroscopic analysis, swelling, chemical and enzymatic degradation studies. Their cell compatibility has been evaluated in vitro by direct and indirect assays on CaCo-2 cells.