Fabrication of Tissue Engineering Scaffold from Hydroxyapatite/Alginate Composite

Abstract

Abstract-Scaffolds for bone tissue engineering must meet the functional requirements, porosity, biocompatibility, and biodegradability. In this study, hydroxyapatite was prepared by wet chemical method and incorporated into the alginate gel solution to improve both the mechanical and cell-attachment properties of the scaffolds. Next, composite scaffolds were fabricated from hydroxyapatite/alginate with different weight ratios by freeze drying method and then some of them coated with triblock copolymer and compared with others. Microstructure observation with SEM suggests the formation of about 50 micrometer size porous structure and interconnected porosity. Then, human mesenchymal stem cells were cultured on the composite scaffolds. Cells adhesion to the scaffolds was observed after three days by DAPI fluorescence microscopy in which more cells adhesion to the coated scaffolds and cells diffusion into the pores are visible. Also, cell adhesion within the structure was observed by SEM in which showed cell attachment was well in depth which confirms DAPI results. These results suggest that the triblock-coated HA/Alg porous scaffolds could provide enhanced cell adhesion and proliferation which may be a promising approach for bone tissue-engineering applications.

Preparation and Characterization of Porous Hydroxyapatite and Alginate Composite Scaffolds for Bone Tissue Engineering

“…Compared to the other methods, freeze-drying is the easiest way to fabricate porous scaffolds. Since freeze-drying can be used for bioceramic and biopolymer materials, freeze-dried structures can produce a wide pore when both materials are used to construct a scaffold [22]. Moreover, with water as the solvent, the process is environmentally-friendly.…”

“…The synthesized HA and the extracted alginate powders were used to prepare the HA/alginate composite scaffolds, based on the freezedrying method adopted from an existing technique [22]. First, the alginate (3% w/v) solution was prepared by dissolving alginate powder in distilled water under stirring (Heidolph MR 3001, Germany) at 900 rpm for 2h, and then HA powder was added to the alginate solution under stirring at room temperature for 2 h. Next, a crosslinker 0.03M CaCl 2 aqueous solution was added drop by drop into the HA/alginate solution under gentle stirring.…”

“…Recently, alginate-based scaffolds, such as HA/alginate and HA/alginate/chitosan composites, have been developed for bone tissue engineering [19,20]. Particularly, HA/ alginate composite scaffolds have been found to increase the pore size of bone [21,22]. Because large pores may be suitable for cell attachment in the inner parts of a scaffold, the HA/alginate scaffold may offer an alternative for bone tissue engineering.…”

Alginic Acid Polymer-Hydroxyapatite Composites for Bone Tissue Engineering

“…It was shown [ 54 ] that ALGH-HAP scaffolds enhance local bone healing because they do not damage liver or kidney functions nor induce carcinogenic or inflammatory effects. From the available literature, it becomes obvious that the development of materials processing techniques, control of scaffold composition, microstructure and HAP particle size plays an important role in the fabrication of advanced ALGH-HAP scaffolds [ 65 , 66 , 67 ] with enhanced biomedical performance.…”