Alginate/Nanohydroxyapatite Scaffolds with Designed Core/Shell Structures Fabricated by 3D Plotting and in Situ Mineralization for Bone Tissue Engineering

Abstract

Composite scaffolds, especially polymer/hydroxyapatite (HAP) composite scaffolds with predesigned structures, are promising materials for bone tissue engineering. Various methods including direct mixing of HAP powder with polymers or incubating polymer scaffolds in simulated body fluid for preparing polymer/HAP composite scaffolds are either uncontrolled or require long times of incubation. In this work, alginate/nano-HAP composite scaffolds with designed pore parameters and core/shell structures were fabricated using 3D plotting technique and in situ mineralization under mild conditions (at room temperature and without the use of any organic solvents). Light microscopy, scanning electron microscopy, microcomputer tomography, X-ray diffraction, and Fourier transform infrared spectroscopy were applied to characterize the fabricated scaffolds. Mechanical properties and protein delivery of the scaffolds were evaluated, as well as the cell response to the scaffolds by culturing human bone-marrow-derived mesenchymal stem cells (hBMSC). The obtained data indicate that this method is suitable to fabricate alginate/nano-HAP composite scaffolds with a layer of nano-HAP, coating the surface of the alginate strands homogeneously and completely. The surface mineralization enhanced the mechanical properties and improved the cell attachment and spreading, as well as supported sustaining protein release, compared to pure alginate scaffolds without nano-HAP shell layer. The results demonstrated that the method provides an interesting option for bone tissue engineering application.

Concentrated gelatin/alginate composites for fabrication of predesigned scaffolds with a favorable cell response by 3D plotting

“…[30][31][32][33] Based on that work, the aim of the present study was to develop novel high concentration plotting materials on the basis of gelatin and alginate for scaffold fabrication. [30][31][32][33] Based on that work, the aim of the present study was to develop novel high concentration plotting materials on the basis of gelatin and alginate for scaffold fabrication.…”

Preparation and properties of dopamine‐modified alginate/chitosan–hydroxyapatite scaffolds with gradient structure for bone tissue engineering

“…[4][5][6] Alginate (Alg), an anionic linear polysaccharide consisting of 1,4-linked β-D-mannuronic acid (M) and α-Lguluronic acid (G) residues, [7][8][9] has been considered as a promising porous scaffold material because of its good biocompatibility, biodegradability, nontoxicity, and nonimmunogenicity. [14][15][16] However, properties to support the bone repair, maintain the stable structure, and provide suitable microstress environment for osteoblasts; (3) suitable biodegradation cycles to match the cell and tissue growth rate without toxic degradation products; (4) good affinity for the scaffolds to the surrounding tissues; and (5) good bone conductivity and osteoinductivity as a template for osteoblasts to grow, proliferate, differentiate, and speed up the repair of defective bone tissue. [14][15][16] However, properties to support the bone repair, maintain the stable structure, and provide suitable microstress environment for osteoblasts; (3) suitable biodegradation cycles to match the cell and tissue growth rate without toxic degradation products; (4) good affinity for the scaffolds to the surrounding tissues; and (5) good bone conductivity and osteoinductivity as a template for osteoblasts to grow, proliferate, differentiate, and speed up the repair of defective bone tissue.…”

Biphasic organo-bioceramic fibrous composite as a biomimetic extracellular matrix for bone tissue regeneration

“…However, studies have demonstrated that HA exhibits poor mechanical properties, including high brittleness and low elasticity thus limiting its application directly as a bone substitute in the bone tissue engineering (9, 10). In view of this, synthesis and characterization of nano sized HA have received intensive interest in nanoscience and nanotechnology (11, 12). However, it needs a supportive biodegradable skeleton such as polycaprolactone (PCL) fibers.…”