Cytocompatible drug delivery devices based on poly[(2-dimethylamino) ethyl methacrylate]/chondroitin sulfate polyelectrolyte complexes prepared in ionic liquids

Important researches aim for the development of efficient and cheaper biomedical devices based on natural polysaccharides. In this facet, polyelectrolytes complexes (PECs) are interesting materials for biomedical purposes because they can be prepared without using conventional and volatile organic solvents and toxic crosslinkers, commonly used in the synthesis of chemical hydrogels. For the first time, we used ionic liquids (1-alkyl-3methylimidazolium tetrafluoroborate ionic liquids, [Bmim][BF4], [Omim][BF4] and [Dmim][BF4]) to prepare poly[(2-dimethylamino) ethyl methacrylate]/chondroitin sulfate (PDMAEMA/CS) PECs in aqueous media. The ionic liquids promoted changes in the PECs morphology, influencing the size of the pore significantly. The presence of ionic liquids in aqueous polyelectrolyte solutions enhanced the interactions between poly[(2dimethylamino) ethyl methacrylate] (PDMAEMA) and chondroitin sulfate (CS), providing organized structures when compared with the PEC yielded only in an aqueous solution. The materials obtained in the ionic liquids' presence were stable and no toxic against epithelial and fibroblast cells. We can modulate the PEC properties by tuning both ionic liquid type and content.