Preparation and characterization of spunlacing silk fibroin/nano-hydroxyapatite composite scaffold

Porous silk fibroin scaffold was first prepared by using spunlacing technique, then nano-hydroxyapatite (HAP)/silk fibroin composite materials were synthesized via in-situ mineralization. HAP showed a uniform rod-like structure, but only granular structures were observed without silk fibroin scaffold, indicating that silk fibroin scaffold can induce the formation of rod-like structures. This was attributed to the electrostatic interactions between carboxyl groups of silk fibroin and Ca2+ in the solution. Thus silk fibroin scaffold plays a dual role of polymer composites substrate and template for HAP in-situ growth. The structure and properties of the composites were characterized by using infrared spectroscopy, X-ray diffraction and mechanical testing. Infrared spectra showed the presence of hydrogen bonding interactions between PO43- of HAP and -NH2 of silk fibroin, while X-ray diffraction patterns suggested that the composites maintained the β-sheet structure and crystallization properties of silk fibroin scaffold. Thus the composites resulted with good mechanical properties and porous structure, which was helpful in osteoblast proliferation and the use as bone repair scaffolds. At the same time, the composite materials showed very well mechanical performance, but easy preparation for large area, low cost, easy to realize industrialization, and will be possible used for bone repair scaffold material widely in future. © 2015, Chongqing Functional Materials Periodical Press Co. Ltd. All right reserved.