Volume 9 Issue 3
Jul.  2024
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Xucai Wang, Dengxian Wu, Wei Liao, Yaxuan Liu, Wenhui Pei, Jixian Wang, Jiayu Gu, Peng Wang, Kai Lan, Caoxing Huang. Constructing osteo-inductive bio-ink for 3D printing through hybridization of gelatin with maleic acid modified bacterial cellulose by regulating addition volumes of maleic acid solution[J]. Journal of Bioresources and Bioproducts, 2024, 9(3): 336-350. doi: 10.1016/j.jobab.2024.04.001
Citation: Xucai Wang, Dengxian Wu, Wei Liao, Yaxuan Liu, Wenhui Pei, Jixian Wang, Jiayu Gu, Peng Wang, Kai Lan, Caoxing Huang. Constructing osteo-inductive bio-ink for 3D printing through hybridization of gelatin with maleic acid modified bacterial cellulose by regulating addition volumes of maleic acid solution[J]. Journal of Bioresources and Bioproducts, 2024, 9(3): 336-350. doi: 10.1016/j.jobab.2024.04.001

Constructing osteo-inductive bio-ink for 3D printing through hybridization of gelatin with maleic acid modified bacterial cellulose by regulating addition volumes of maleic acid solution

doi: 10.1016/j.jobab.2024.04.001
Funds:

This study was supported by National Basic Research Program of China (No.2021YFA1201404),National Natural Science Foundation of China (No.32271413),Science program of Jiangsu Province Administration for Market Regulation (No.KJ2024010).

  • Publish Date: 2024-07-05
  • Bacterial cellulose (BC) is an exopolysaccharide with unique properties that has been applied in various fields. However, the dense and intertwined nature of BC fibers limits its use in certain applications, including 3D printing scaffolds for bone regeneration. In this work, a controllable BC-based bio-ink for 3D printing was successfully prepared by modifying the neat BC through maleic acid (MA) treatment, aiming to promote bone tissue regeneration. To achieve homogeneous BC dispersions while preserving its crystalline and chemical properties, BC was modified by MA solution (60 %, w/V) with solid-liquid ratio from 1:5 to 1:50 (w/V) to obtain MA-BC dispersions. The analysis results from microstructure, chemical group, crystallinity, and wettability indicated that the BC/MA solution with ratio of 1:30 demonstrated the best pre-treatment performance to obtain MA-BC. Subsequently, by combining MA-BC with gelatin, we successfully formulated MA-BC-GEL gels with favorable rheological properties and compression modulus, which can be used as promising bio-inks for 3D bioprinting applications. In vitro tests demonstrated 1:30 MA-BC possessed excellent biocompatibility, a significant ability to express the alkaline phosphatase gene and osteogenic-related genes, and facilitated the formation of mineralized nodules. The utilization of this novel bio-ink in scaffold preparation for bone regeneration highlights the promising application of modified BC in bone tissue engineering field.

     

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