Abstract：The biological scaffolds of tissue engineering are required to have good biocompatibility, matched mechanical properties, as well as morphology and microstructure for cell growth and reproduction. Although a large number of biomaterials have been developed to prepare tissue-engineering scaffolds, the forming problems and poor mechanical properties of the scaffolds still seriously limit the development of tissue engineering. The sodium alginate was used as raw material, and its mechanical properties were enhanced by agarose. The structure and morphology of sodium alginate/agarose composite hydrogels with different ratios were studied,the mechanical properties were tested. In addition, the composite hydrogel scaffold was formed by direct ink writing, and the size of the microscopic pores in composite hydrogels were designed and observed. The results show that the composite hydrogels with different ratios have little difference in water content, all around 90%. Apart from the pure agarose gel and the composite gel with a volume ratio of 1：2, the surface and cross section of the composite gel in other ratios are relatively rough. Agarose can enhance the composite gel to a certain extent, and the composite gel with the volume ratio of sodium alginate to agarose of 2：1 has the highest compression modulus, which can reach 0.353 MPa. The decomposition of calcium carbonate created submicron pores in the composite hydrogel,therefore the prepared composite hydrogel has rough surface and micro-pores,which is conducive for cell growth and reproduction.
汤桂平, 严倩, 刘洁, 宋波, 文世峰, 史玉升. 3D打印琼脂糖和海藻酸钠复合水凝胶组织与性能研究[J]. 材料工程, 2021, 49(5): 66-74.
TANG Gui-ping, YAN Qian, LIU Jie, SONG Bo, WEN Shi-feng, SHI Yu-sheng. Microstructure and properties of 3D printed agarose and sodium alginate composite hydrogel. Journal of Materials Engineering, 2021, 49(5): 66-74.
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