Nano-silver in situ hybridized collagen scaffolds for regeneration of infected full-thickness burn skin

Nano hybrid materials have attracted extensive attention in the biomedical field. However, it is still a challenge to make biofunctional nanoparticles homogenously distributed in 3D scaffolds. In this research, histidine (His) was covalently cross-linked into collagen (Coll) scaffolds and the imidazole derived from His was employed as a template to chelate silver ions which were then reduced in situ to form silver nanoparticle (Ag NP)-hybridized Coll scaffolds. The resultant nanocomposite demonstrated an increased mechanical strength and the Ag NPs showed a narrow size distribution and were dispersed homogeneously in the 3D Coll/His scaffolds. Moreover, these hybrid scaffolds exhibited better biocompatibility and antibacterial properties against both Gram positive and Gram negative bacteria than Coll scaffolds. The Coll/His/Ag NPs scaffolds were transplanted to the infected full-thickness burn skin of the SD rat model; the results revealed excellent regeneration effects after three weeks compared with the groups not treated with Ag NPs. This study has offered a facile method to construct functional nanoparticle hybridized scaffolds for efficiently healing infected wounds.