Role of silk fibroin and rice starch on some physical properties of hydroxyapatite-based composites

Abstract

© 2015 Wiley Periodicals, Inc. The role of organic blends of silk fibroin (SF) and rice starch (RS) in bone composites based on inorganic hydroxyapatite (HA) is studied. The physical property of HA-based composites prepared by using the sol-gel method from Ca(OH)<inf>2</inf> and H<inf>3</inf>PO<inf>4</inf> in ethanol and water solvent (4: 1 volume ratio) could be improved by adding SF and RS (1: 2 weight ratio) to HA (7: 3 weight ratio). The Fourier transform infrared spectrometer spectrum shows that the SF and RS organic phases are blended homogeneously into the HA crystal structure. Addition of SF increases the pore size and surface area of the composites, as measured by Brunauer-Emmett-Teller method, but their pore volume is slightly decreased. The values of lattice parameters, crystallinity, and crystallite size, as determined from the field-emission scanning electron microscope, transmission electron microscope, and X-ray diffractometer results, increase after adding RS. The results are agreeable with the increase of their compressive strength and Young's modulus. Thus, the improved physical property of the prepared HA-SF/RS composites is better suited as bone-filling material than the standard HA or HA-based composites with either SF or RS only. Therefore, due to its low cost, biocompatibility, and nontoxicity, this innovative solution could be worth taken under consideration by the restorative dental and orthopedic implants industry.