In vitro properties of nano-hydroxyapatite/chitosan biocomposites

In vitro behavior of the composites was performed in simulated body fluid (SBF) to induce the formation of bone-like apatite layer onto their surfaces and its enhancement in the presence of citric acid (CA). The results proved the mineralization of calcium (Ca2+) and phosphorus (P) ions onto the composites which contain high chitosan concentration especially after longer time of immersion. The degradation data decreased with increase chitosan content especially C2 composites (containing 30% chitosan) and highly decreased in the presence of CA which increased binding strength through the composite. The swelling % increased with increase of chitosan content in HA composite but it decreased with CA addition as increase of interaction between three matrices. The Fourier Transformed Infrared Spectroscopy (FT-IR) and Scanning Electron Microscope (SEM-EDAX) confirmed the formation of bone-like apatite layer on the surface of the composites especially these containing CA. These biocomposites have unique in vitro properties for bone substitute's applications in the future.