Chitosan-Based Zwitterionic Polyelectrolytes and Their N-Phosphobetainates： Facile Synthesis and Aqueous Solution Behaviors

Chitosan has remarkable potential applications in pharmaceutical and cosmetic formulations, e.g. for drug delivery systems, tissue engineering, transplant and cell regeneration due to its excellent biocompatibility, biodegradability, mucoadhesion, etc. Its major drawback as considered for pharmaceutical and cosmetic formulations is its poor solubility due to strong hydrogen bonding and compact structures. Considerable efforts were focused on improving its solubility and enforcing its functionality. As well-known that phosphorylcholine （PC）, the structural component of cell membrane, is an amphiphile containing the zwitterionic quaternary ammonium and phosphonic acid moieties （phosphobetaine groups）. There has been an intensive effort over the past decades to prepare and explore potential applications of the synthetic PC-polymers.