BIOMACROMOLECULES IN RADICAL PROCESSES: INNOVATIVE STRATEGIES FOR THE SYNTHESIS OF BIOMATERIALS

Natural polymers, such as polysaccharides and proteins, are materials extensively investigated due to their biocompatibility, biodegradability and non-toxic and non-immunogenic characteristics. Enclosing the biomacromolecules, in a complex structure, these features can be transferred to a biomaterial in order to extend the performance of the device. Basically, the synthesis of bioconjugates, by insertion of natural polymers in a macromolecular network by radical polymerization processes, can be achieved employing two different synthetic approaches. The first method involves the chemical modification of the biomacromolecules to introduce functionality able to undergo radical polymerization reactions. In addition, polysaccharides and proteins, without any functional changes, can take part in graft radical polymerization reactions that involve the heteroatoms of the substrates. Both synthetic approaches allows to prepare biocompatible bioconjugates showing improved physico-chemical and mechanical properties respect to the starting natural species. Furthermore, radical polymerization of biomacromolecules with monomeric species bearing specific functionality, carry out to the synthesis of polymeric network that undergo a phase transition process in response to external stimuli changes (temperature, pH, magnetic and electric field). These findings showed that the radical polymerization techniques, improving the performance of natural polymer, represent an innovative tools for the preparation of macromolecular devices potentially useful in pharmaceutical and biomedical field.