Chitosan–hydroxyapatite composite biomaterials made by a one step co-precipitation method: preparation, characterization and in vivo tests

摘要

A series of biocompatible chitosan/hydroxyapatite composites has been synthesized in anaqueous medium from chitosan solution and soluble precursor salts by a one-stepcoprecipitation method. The composite materials were produced in dense and porousvariants. XRD and IR studies have shown that the apatite crystals in the composites havestructural characteristics similar to those of crystals in biogenic apatite. A study of in vivobehaviour of the materials was carried out. Cylindrical rods made of the chitosan/hydroxyapatite composite material were implanted into the tibial bones of rats. After 5, 10, 15and 24 days of implantation, histological and histo-morphometric analyses of decalcifiedspecimens were undertaken to evaluate their biocompatibility and the possibility to applythem in bone tissue engineering. The calcified specimens were examined by scanningelectron microscopy combined with X-ray microanalysis to compare the elementalcomposition and morphological characteristics of the implant and the bone duringintegration. Porous specimens were osteoconducting and were replaced in vivo by newlyformed bone tissue.