With silk fibroin and vancomycin (VCM) as carrier and drug model, respectively, we prepared silk fibroin microspheres (SFM) with different concentration using the water-in-oil emulsion solvent diffusion method. We further developed VCM loaded calcium sulfate hemihydrates (CSH)/SFM artificial bone composites. In this study, surface morphology of the materials was observed using scanning electron microscope (SEM). Structure of the materials was studied with Fourier transform infrared spectroscopy (FTIR). Antibacterial activity of the materials was validated with the inhibition zone test. Drug release property of materials was evaluated using ultraviolet/visible spectrophotometry. Mechanical property of the materials was tested using computer-controlled electronic universal testing machine. The results showed that silk fibroin concentration had no significant effect on molecular conformation and antibacterial property of the SFM. The average diameter of SFM increased and the release rate decreased gradually as the silk fibroin concentration increased. The release rate decreased and the compressive fracture work increased as the silk fibroin concentration increased when adding SFM to CSH. This composite had partly corrected the disadvantages of CSH including the high brittleness and initial burst release. The research would have a good application foreground in the clinical treatment of infectious bone defect.
ObjectiveTo study the preparation and properties of the hyaluronic acid (HA)/α-calcium sulfate hemihydrate (α-CSH)/β-tricalcium phosphate (β-TCP) material (hereinafter referred to as composite material). Methods Firstly, the α-CSH was prepared from calcium sulfate dihydrate by hydrothermal method, and the β-TCP was prepared by wet reaction of soluble calcium salt and phosphate. Secondly, the α-CSH and β-TCP were mixed in different proportions (10∶0, 9∶1, 8∶2, 7∶3, 5∶5, and 3∶7), and then mixed with HA solutions with concentrations of 0.1%, 0.25%, 0.5%, 1.0%, and 2.0%, respectively, at a liquid-solid ratio of 0.30 and 0.35 respectively to prepare HA/α-CSH/ β-TCP composite material. The α-CSH/β-TCP composite material prepared with α-CSH, β-TCP, and deionized water was used as the control. The composite material was analyzed by scanning electron microscope, X-ray diffraction analysis, initial/final setting time, degradation, compressive strength, dispersion, injectability, and cytotoxicity. ResultsThe HA/α-CSH/β-TCP composite material was prepared successfully. The composite material has rough surface, densely packed irregular block particles and strip particles, and microporous structures, with the pore size mainly between 5 and 15 μm. When the content of β-TCP increased, the initial/final setting time of composite material increased, the degradation rate decreased, and the compressive strength showed a trend of first increasing and then weakening; there were significant differences between the composite materials with different α-CSH/β-TCP proportion (P<0.05). Adding HA improved the injectable property of the composite material, and it showed an increasing trend with the increase of concentration (P<0.05), but it has no obvious effect on the setting time of composite material (P>0.05). The cytotoxicity level of HA/α-CSH/β-TCP composite material ranged from 0 to 1, without cytotoxicity. Conclusion The HA/α-CSH/β-TCP composite materials have good biocompatibility. Theoretically, it can meet the clinical needs of bone defect repairing, and may be a new artificial bone material with potential clinical application prospect.