Controlled release of IgG by novel UV induced polysaccharide/poly(amino acid) hydrogels

The development of new protein and peptide drugs needs new delivery systems able to entrap such drugs in safe conditions without affecting their structure and biological activity. In this context, the present work reports a new approach to load IgG, used as a model of therapeutic proteins such as anti-TNF-alpha monoclonal antibodies, into a polymeric system able to release the entrapped IgG in a controlled manner. In particular, new polysaccharide/poly(amino acid) UV induced hydrogels are proposed as colon delivery systems for human IgG. The poly(amino acid), alpha,beta-poly[N-(2-hydroxyethyl)-D,L-aspartamide], has been functionalized with methacrylic anhydride, while the polysaccharide, inulin, has been functionalized with methacrylic anhydride and succinic anhydride. The hydrogels were obtained by a short-time UV irradiation, in physiological-like conditions, without the use of radical initiators, at low temperature and in the presence or in the absence of PEGDM(550) used as a co-crosslinker in order to evaluate potential differences in terms of physicochemical properties and release profile. The obtained hydrogels were degradable by inulinase, showed a high cell compatibility and the released antibodies, analyzed by SEC and ELISA, retained their biological activity.