Synthesis of Porous Carbonate Apatite/Gelatin Scaffolds Via Freeze Drying Method

Abstract

Gelatin is widely used in medical field as scaffolding material. However, in order to encourage bone formation, carbonate apatite (CO3Ap) which resembles the human bone composition is added into the gelatin scaffold. In this research, CO3Ap/gelatin scaffold were fabricated via freeze drying method. CO3Ap powder was obtained from precipitation reaction of calcium hydroxide and phosphoric acid accompanied by carbon dioxide gas as the carbonation source. The obtained powder were then analysed by X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy and carbon hydrogen nitrogen (CHN) test. The carbonate content by weight percentage is 12.8 wt. %. The mean particle size of the CO3Ap powder was 7.76 μm. To fabricate the CO3Ap/gelatin scaffold, the CO3Ap powder were mixed with gelatin at various CO3Ap/gelatin ratio (15/5, 10/10) wt. % followed by casting and pre-freezing temperature of -10 °C, -20 °C and -40 °C before freeze dried. The highest compressive strength achieved was 7412.36 kPa for CO3Ap/gelatin with ratio (10/10) wt. %, freeze at -40 °C as the pre-freezing temperature. Field emission scanning electron microscope (FESEM) analysis shows that the CO3Ap powder was distributed within the gelatin scaffold. As a conclusion, it was found that higher gelatin content and lower pre-freezing temperature increases the compressive strength of the CO3Ap/gelatin scaffold.