Design of Highly Porous Materials Based on Chitosan/Pectin Interpolyelectrolyte Complex for Wound Healing Application

Interpolyelectrolyte complexes (IPECs) of polysaccharides are multifunctional polymer materials that improve the mechanical and physicochemical properties of individual polysaccharides. In this study, highly porous (>90%) materials based on IPECs of versatile natural polysaccharides, chitosan (30 and 1,200 kDa) and pectin, are obtained by freeze-drying technique. To enhance the interaction between chitosan and pectin macromolecules, the latter are chemically functionalized with dialdehyde groups. The chitosan-/aldehyde-functionalized pectin (Chit/AF-Pect) polyelectrolyte complex sponges obtained are characterized using SEM, FTIR spectroscopy, and TGA. The swelling capacity study reveals a higher swelling ratio of IPEC sponges with an increase in both the molecular weight and content of chitosan: for Chit30/AF-Pect, the swelling ratio rises from 327% to 480%, while for Chit1200/AF-Pect, from 681% to 1,066%. Additionally, the in vitro degradation test demonstrates higher stability of Chit1200/AF-Pect sponges in comparison with those of Chit30/AF-Pect: after 4 days of incubation, the weight losses are found to be 9%–16% and 18%–41%, respectively. The cytotoxicity study shows that Chit30/AF-Pect sponges are noncytotoxic, with cell viability values >70%. Furthermore, the Chit30/AF-Pect sponges, obtained at chitosan:pectin weight ratio of 5:1, exhibit bactericidal activity against Escherichia coli BIM B-984 G, Pseudomonas aeruginosa BIM B-807 G, Staphylococcus aureus BIM B-1841, and slightly inhibit the growth of Enterococcus faecalis BIM B-1530 G. These findings indicate that the obtained Chit30/AF-Pect sponges can be used to create wound dressings for wound healing applications.