Hydroxyapatite/sodium Hyaluronate/konjac Glucan-mannan Chitosan Porous Scaffold Preparation And Research

Hydroxyapatite (HAP), which is the main inorganic component of human bone. As bone implant material, it appears good biological compatibility, biological activity, and good bone conductivity. But HAP scaffold has some shortcomings such as poor mechanical properties and formability, and will spread easily after implanting into the body. Konjac glucomannan (KGM) is a kind of plant polysaccharide, which exhibit excellent mechanical properties and formability. As Sodium hyaluronate (SH) exhibit good biological characteristics, and is similar to KGM in microstructure, physical and chemical performance, it is estimated that they can compound properly. This article discuss the advantage and meaning integrating HAP, KGM and SH, moreover do some deep research by experiment result.Experimental composed two main parts as follows:1. Firstly, HAP powders were prepared by double titration method. HAP and KGM powders were included in SH gel to prepare the scaffolds with ammonia to regulate pH value, via sol-gel method. Curing and alkaline removing were performed under water bath, fabricated the composite scaffolds by freeze-drying method. The nano-HAP powders were characterized by X-ray diffraction (XRD), Fourier Transform-Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM) were used to investigate morphology of the composite scaffolds. Porosity, pore size, compressive strength, and in vitro degradation rate of the scaffolds were tested. The BMSCs culture experiment was performed in order to investigate the biological property of the scaffolds.Results:The scaffolds prepared above were three-dimensional network-like porous structure with the central pore size of scaffolds situated between110μm to185μm. The porosity was between69%to97%. The compressive strength was found0.48Mpa to2.24Mpa. The weight of SH was the maximum factor, the volume of ammonia water was more effective, and the effect of the weight of n-HAP and KGM were smallest. The best experiment program of scaffold is:0.02g SH,1.5g KGM, 0.12ml ammonia water, the content of n-HAP is10%. HAP, SH and KGM composed the scaffolds with common form. The hydroxyapatite particles were different shapes and sizes with low crystallinity and serious reunion phenomenon. The scaffolds could degradate about60%after12weeks. The results of BMSCs culture shown that scaffolds have good stem cells compatibility. In a word, this HAP/SH/KGM scaffolds exhibit potention to be used as bone tissue engineering scaffolds.2. The scaffolds were prepared using biomimetic synthesis. The SH/KGM porous scaffolds were prepared with SH and KGM via gellation method. Ammonia was used as crosslinker in the gellation process. The composites were pretreated with calcium containning sollution and then biomimetic mineralized in Simulated Body Fluid (SBF). The scaffolds were characterized by XRD, FTIR and SEM, in order to investigate morphology of the composite scaffolds. Porosity, pore size, compressive strength, and in vitro degradation rate of the scaffolds were tested. The BMSCs culture experiment was performed in order to investigate the biological property of the scaffolds.Results:The only scaffolds which were pretreated into Ca(NO3)2solution can sedimentary hydroxyapatite crystals. The hydroxyapatite particles were uniform spherical crystals with low crystallinity and small diameters. KGM formed a three-dimensional network structure after deacetylation. HAP, SH and KGM composed the scaffolds with common form and electrostatic bonding. The scaffolds could degradate about70%after12weeks. And the results of BMSCs culture shown that scaffolds exhibit good stem cells compatibility.All these results show that, comparing with the scaffolds prepared with the compounding method, the biocomposites exhibit better properties. In a word, the bio-mineralized SH/KGM porous scaffolds are novel bone substitution materials with great potentials.