Preparation and characterization of printed magnesium scaffolds for bone tissue engineering

doi:10.3969/j.issn.2095-4344.0054

Abstract

Abstract:

BACKGROUND: The traditional methods for preparing magnesium scaffolds include casting, powder metallurgy and laser processing technology. But these methods have some defects in pore connectivity, structure complexity, and personalization. Therefore, it is of great importance to explore a new method for the preparation of porous magnesium scaffolds.

OBJECTIVE: To investigate the preparation and characterization of porous magnesium scaffolds fabricated by three-dimensional (3D) printing technology.

METHODS: A magnesium porous scaffold was prepared by 3D printing. The high-stability magnesium paste (consisting of magnesium powder, 2-hydroxyethyl cellulose, polyethylene glycol, glycerol trioleate, ammonia, deionized water and absolute ethanol) was extruded from the pneumatic extrusion printing system to construct the scaffold, which was then sintered under protective atmosphere. The scaffold microstructure was observed by scanning electron microscope. The phase composition of scaffold was observed by X-ray diffraction. The porosity was measured by drainage method. The compressive strength was measured by universal testing machine. The degradation was studied by immersing the scaffold in saline for 30 days, and the degradation rate and the pH value of soak solution were measured at regular intervals.

RESULTS AND CONCLUSION: (1) The magnesium scaffold was piled up by cylindrical filaments, and both the sizes of filaments and the pores were (450±50) μm. Also, there were many micropores in the filaments that formed the secondary pores. The porosity of the scaffold was (65.0±2.5)% and the compressive strength was (0.87±0.15) MPa. The principal phase of the scaffold was magnesium. (2) The degradation of the scaffold continued with the soaking time, and the degradation rate showed a steady trend, which was (10±0.2) mm per year in average. The pH value of the soak solution increased in the first 5 days, and then the pH value was kept at 10.5±0.2. To conclude, 3D printing technology provides a new method for porous magnesium scaffold preparation and application in bone tissue engineering.

中国组织工程研究杂志出版内容重点：生物材料；骨生物材料; 口腔生物材料; 纳米材料; 缓释材料; 材料相容性；组织工程

Key words: Biodegradable Materials, Magnesium, Tissue Engineering

CLC Number:

R318

Li Ying, Wu Quan, Tang Geng, Li Hong, Shang Li-yan. Preparation and characterization of printed magnesium scaffolds for bone tissue engineering[J]. Chinese Journal of Tissue Engineering Research, 2018, 22(6): 827-832.

Figures/Tables 8

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