Ti 3 C 2 T x MXene-incorporated macroporous bacterial cellulose scaffolds with physical and chemical crosslinking for enhanced mechanical and biological performance

Macroporous bacterial cellulose (MBC) scaffolds composed of BC fragments have received much attention in bone tissue engineering due to their simplicity in preparation process. However, the use of BC fragments and the sole polysaccharide component of BC inevitably lead to MBC scaffolds with low mechanical properties and inadequate biocompatibility and osteogenic property. Herein, physically and chemically crosslinked macroporous BC/Ti 3 C 2 T x (pc-MBC/Ti 3 C 2 T x ) scaffolds were successfully prepared by combining physical and chemical crosslinking strategies. The simultaneous physical crosslinking (hydrogen bonds between Ti 3 C 2 T x nanosheets and the nanofibers of BC fragments) and chemical crosslinking (amide bonds among the residual trace proteins on the nanofibers of BC fragments) exhibit an obvious synergistic effect on the improvement of mechanical properties of pc-MBC/Ti 3 C 2 T x scaffolds. The maximum compressive strength (124.28 ± 5.04 kPa at 80% strain) and modulus (40.78 ± 3.01 kPa) of pc-MBC/Ti 3 C 2 T x scaffold are about 3–9 and 3–10 times as high as the counterparts, respectively. In addition, the interconnected macropores can effectively support the migration and penetration of MC3T3-E1 cells into pc-MBC/Ti 3 C 2 T x scaffolds. More importantly, pc-MBC/Ti 3 C 2 T x scaffolds are superior to the counterpart without Ti 3 C 2 T x nanosheets in terms of viability, adhesion, spreading, and osteogenic differentiation of MC3T3-E1 cells. These obtained results indicate that pc-MBC/Ti 3 C 2 T x scaffolds hold considerable potential for bone tissue engineering.