Biomimetic fabrication of mineralized composite films of nanosilver loaded native fibrillar collagen and chitosan

Silver nanoparticles loaded fibrillar collagen-chitosan matrix (CC) was prepared by biomimetic approach by blending silver nanoparticles (tAgNPs), collagen fibril and chitosan hydrogel followed by cross-linking and biomineralization. Electron micrograph showed that the surface of the composites exhibited native fibrillar morphology of collagen and their cross-section revealed layer-like arrangement of native fibrillar collagen. The mineralized composites exhibited surface mineralization of calcium phosphates incorporated with magnesium. FT-IR ATR analysis revealed the uniform blending of collagen and chitosan without any chemical interaction between them. XRD analysis showed incorporation of silver nanoparticles and lamellar structure of collagen and chitosan. The mechanical property of the dry composite film showed increase in tensile strength with the addition of chitosan and raised to 4.6 fold in M-CC4 composite. The incorporation of chitosan in M-CC3 led to 2.2 fold increase in mineralization as confirmed by the TGA analysis. Contact angle analysis revealed the hydrophilic nature of the composite. Hemolysis analysis of the composites verified the hemocompatible nature of composites with hemolysis < 5%. MTT assay for the composites was carried by seeding MG-63 cells and indicated cell viability > 80%. Antibacterial activity analysis showed the percent growth inhibition of about 27% and 37% for S. aureus and E. coli respectively. The prepared composite would possess silver nanoparticles loaded collagen fibril in the native state and the formed biomineral will be similar to the bone mineral. Hence the fabricated composite-could be used as a biomaterial for bone tissue engineering applications.