Effects of character of silk fibroin on properties of calcium phosphate cement

The mechanical properties of calcium phosphate cement(CPC) were improved by adding silk fibroin with different characters.The structure of the resulted product was investigated by X-ray diffraction and Fourier transform infrared spectroscopy.Its surface morphology was observed by scanning electron microscopy.The porosity of the product was measured by drainage method and the mechanical properties were tested by instron universal testing machine.The results showed that the products of hardening reaction of CPC containing silk fibroin were similar to that of pure CPC,and hydroxyapatite produced in both reactions.Silk fibroin with different character significantly improved the flexural strength of CPC.The character of the silk fibroin had distinct effects on the work-of-fracture,and the work-of-fracture of CPC by silk fibers increased significantly,which was 7-21.8 times of that of pure CPC.The character of the silk fibroin had no significant effects on the structure,but the porosity slightly decreased.