Engineering conductive antioxidative antibacterial nanocomposite hydrogel scaffolds with oriented channels promotes structure-functional skeletal muscle regeneration

• A multifunctional hydrogel scaffold with ordered channels (FAPu) was fabricated. • FAPu showed injectable conductive antioxidant antibacterial activities. • FAPu possessed biomimetic conductive and elastomeric behaviour. • FAPu efficiently enhanced myogenic differentiation and myofiber formation. • FAPu promoted structural and functional regeneration of skeletal muscle in vivo . It remains a challenge for the structure–function regeneration of volumetric skeletal muscle loss, in addition to the conservative treatment. Herein, we report an injectable conductive antioxidant antibacterial nanocomposite hydrogel scaffolds for the structural and functional regeneration of full-thickness skeletal muscle tissues. The nanocomposites hydrogel scaffolds (FPAu) were fabricated through the double crosslinking of F127-CHO network using ultrasmall gold@polymine nanoparticles and polydopamine nanoparticles. FPAu hydrogel scaffolds showed the good antioxidant activity, antibacterial ability, electroconductive activity and well-ordered porous structure, which significantly upregulated the myogenic genes and myosin heavy chain (MHC) protein expression of C2C12 myoblasts, as well as the myotube formation in vitro . Importantly, by a rat tibialis anterior muscle defect model, FPAu scaffolds facilitated the skeletal muscle tissue formation, restored the mechanical and electrophysiological functions of skeletal muscle tissues. This work suggests that engineering the injectable conductive antioxidant scaffolds with good porous structure is a promising strategy for in situ muscle tissue engineering.