Desenvolvimento de biocompósitos rígidos para aplicação como biomaterial.

Abstract

The hydroxyapatite is one of the most biocompatible materials known by encouraging bone growth. However, the main drawback it is the poor mechanical strength. A method to overcome this problem is the addition of the biopolymer chitosan, suitable for applications as biomaterials. In this study was obtained a hydroxyapatite - chitosan biocomposites for application as a biomaterial. To obtain the biocompositos, hydroxyapatite granules were added under constant stirring in a solution of chitosan in quantities necessary to obtain a product with a ratio 70:30 (HA/CS). Then the paste formed was filtered and pressed to obtain the biocomposite disk. The analysis of scanning electron microscopy (SEM) of the biocomposite HA/CS, indicated that there was a good dispersion of particles of HA chitosan in the presence of small pores on the surface of the sample. XRD results showed no significant change in the profile of hydroxyapatite (HA) with the incorporation of chitosan. It was observed in the analysis by Infrared Spectroscopy with Fourier Transform (FTIR) bands characteristic of hydroxyapatite, as well as bands that characterize the interaction between chitosan and hydroxyapatite. According with the analysis of water absorption the biocomposites HA/CS showed water absorption of approximately 48.365%. The biocompatibility of biocomposites HA/CS was confirmed with the MTT assay, where did not reveal a toxicity of same. The biocomposites presented mechanical strength values lower than those reported in literature for use in cortical bone, the mechanical strength obtained at different processing conditions allow its use in spongy bone replacement. According with results, we can concluded that the obtained had biocomposites, the morphological point of view, features dense showed no toxicity, they maintained their crystallographic features demonstrated interactions between the compounds and had mechanical properties which fall between the values reported for compact and spongy bone, which allows an application to replacement of spongy bone.