Science China Life Sciences

, Volume 62, Issue 12, pp 1670–1682 | Cite as

Supercritical fluid-assisted controllable fabrication of open and highly interconnected porous scaffolds for bone tissue engineering

  • Hanxiao Tang
  • Ranjith Kumar Kankala
  • Shibin Wang
  • Aizheng ChenEmail author
Research Paper


Recently tremendous progress has been evidenced by the advancements in developing innovative three-dimensional (3D) scaffolds using various techniques for addressing the autogenous grafting of bone. In this work, we demonstrated the fabrication of porous polycaprolactone (PCL) scaffolds for osteogenic differentiation based on supercritical fluid-assisted hybrid processes of phase inversion and foaming. This eco-friendly process resulted in the highly porous biomimetic scaffolds with open and interconnected architectures. Initially, a 23 factorial experiment was designed for investigating the relative significance of various processing parameters and achieving better control over the porosity as well as the compressive mechanical properties of the scaffold. Then, single factor experiment was carried out to understand the effects of various processing parameters on the morphology of scaffolds. On the other hand, we encapsulated a growth factor, i.e., bone morphogenic protein-2 (BMP-2), as a model protein in these porous scaffolds for evaluating their osteogenic differentiation. In vitro investigations of growth factor loaded PCL scaffolds using bone marrow stromal cells (BMSCs) have shown that these growth factor-encumbered scaffolds were capable of differentiating the cells over the control experiments. Furthermore, the osteogenic differentiation was confirmed by measuring the cell proliferation, and alkaline phosphatase (ALP) activity, which were significantly higher demonstrating the active bone growth. Together, these results have suggested that the fabrication of growth factor-loaded porous scaffolds prepared by the eco-friendly hybrid processing efficiently promoted the osteogenic differentiation and may have a significant potential in bone tissue engineering.


supercritical foaming polycaprolactone bone tissue engineering osteogenic differentiation bone morphogenic protein-2 


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This work was supported by the National Natural Science Foundation of China (U1605225, 31570974, and 31470927), the Public Science and Technology Research Funds Projects of Ocean (201505029), the Promotion Program for Young and Middle-aged Teacher in Science and Technology Research of Huaqiao University (ZQN-PY107) and the Program for Innovative Research Team in Science and Technology in Fujian Province University.

Compliance and ethics The author(s) declare that they have no conflict of interest.

Supplementary material

Supplementary material, approximately 15.1 MB.


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Copyright information

© Science China Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  • Hanxiao Tang
    • 1
  • Ranjith Kumar Kankala
    • 1
    • 2
    • 3
  • Shibin Wang
    • 1
    • 2
    • 3
  • Aizheng Chen
    • 1
    • 2
    • 3
    Email author
  1. 1.College of Chemical EngineeringHuaqiao UniversityXiamenChina
  2. 2.Institute of Biomaterials and Tissue EngineeringHuaqiao UniversityXiamenChina
  3. 3.Fujian Provincial Key Laboratory of Biochemical Technology (Huaqiao University)XiamenChina

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