Double network microcrystalline cellulose hydrogels with high mechanical strength and biocompatibility for cartilage tissue engineering scaffold

Cartilage tissue regeneration is tremendously tough, it has become a major clinical challenge for the orthopedic medical community. Because of their bionic structure, high water content, biocompatibility, and biodegradability, hydrogels derived from natural polysaccharide are excellent candidates for cartilage tissue engineering. However, these materials often face problems such as poor mechanical strength and excessive swelling, which limit their clinical application. This study used a chemical-physical multi-step cross-linking strategy to create double-network (DN) microcrystalline cellulose (MCC) hydrogels. The hydrogels' intrinsic biomimetic macroporous shape and high water content made them ideal for chondrocyte adhesion and proliferation. The performance requirements for cartilage tissue engineering scaffolds are met by DN hydrogels, which have a sufficiently high compressive strength (4.53 MPa), superior compression recovery, and fatigue resistance, compared to single-network (SN) hydrogels. According to in vitro findings, DN hydrogels could boost cell adhesion and proliferation due to their safe and non-toxic nature. Hydrogels were demonstrated to be stable over the long-term performance, to degrade slowly, and to have strong histocompatibility by in vivo implantation. To construct cartilage tissue engineering scaffold and conduct three-dimensional cell culture, DN hydrogels have significant potential.