Bioactivity examination for calcium phosphate-chitosan composites in simulated body fluid Pembimbing

Abstract

Calcium phosphate-chitosan composites such of biomaterial that had biodegradable and bioactivity characteristics, therefore it potentially to make a biomaterial of bone substitution. This study aimed to synthesize calcium phosphate-chitosan composites and examine that composites had both of characteristics with in vitro evaluation by immersion in Simulated Body Fluid (SBF). Calcium phosphate was prepared by precipitation of Ca from eggshell which was dropped by ((NH4)2HPO4) at temperature 37oC. Molar ratio Ca and P was calculated approximately 0.3 M and 0.18 M for each volume 100 ml. Result of precipitation was precipitated 24 hours then was filtered. Precipitation results was dried at temperature 110oC for 5 hours then at 900oC for 5 hours to resulting hydroxyapatite (HAp) and at temperature 110oC for 5 hours to resulting carbonated apatite (AK). Calcium phosphate-chitosan composites was prepared by sonication method. Optimate composition of calcium phosphate-chitosan composites were 64% HAp, 16% AK, and 20% chitosan. Composition was sonicated for 3 hours untill homogen. Sonication results was dried in incubator at temperature 50ºC for 15 hours. In vitro by immersion in SBF was prepared by increasing consecutively KCl, NaCl, NaHCO3, MgSO4.7H2O, CaCl2, Tris+HCl, NaN3, and KH2PO4 then added aquabidest 100 ml. Composites was formed as a pellet then immersed in 50 ml SBF in petridish for 3 months and was observed for each week. Biodegradable characteristics results showed that there were alteration of weight-loss in composites. Bioactivity showed by X-Ray Diffraction (XRD), Fourrier Transform Infrared (FTIR), and Scanning Electron Microscophy (SEM). X-Ray Diffraction results showed that alteration phase mostly to HAp but there were fluctuative rate on crystallinity degree. FTIR spectra indicated that the longer the time of immersion, compositions for each chemical functions was decreased and it supported by SEM results that showed by the greater agglomerated particles and cavity in the longer time. Based on result, after in vitro evaluation by immersion in SBF indicated that calcium phosphate-chitosan composites had biodegradable and bioactivity characteristics it caused there were some interactions between composites and SBF.