A semi-interpenetrating network polyampholyte hydrogel simultaneously demonstrating remarkable toughness and antibacterial properties

Abstract

Hydrogels have likely not made widespread penetration in biomedical engineering work due to several key hurdles such as poor mechanical strength and non-existent antimicrobial properties. A new semi-interpenetrating polymer network (Semi-IPN) hydrogel was prepared by interpenetrating carboxymethyl chitosan (CMCH) with acrylamide (AM) and maleic acid (MA) by covalent bond crosslinking enhanced by ionic (carboxylic–Fe³⁺) secondary crosslinks. These hydrogels show a good tensile stress of about 1.44 MPa as well as outstanding antibacterial activity against Staphylococcus aureus and Gram-negative E. coli because of CMCH.