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Stiffness memory nanohybrid scaffolds generated by indirect 3D printing for biologically responsive soft implants
Linxiao Wu1, Jatinder Virdee1, Elizabeth Maughan2
1UCL Centre for Nanotechnology and Regenerative Medicine, Division of Surgery & Interventional Science, University College London, London NW3 2PF, UK.
Acta Biomaterialia
|September 18, 2018
Summary
We developed thermoresponsive polymer scaffolds with
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Tissue Engineering
- 3D Printing
Background:
- Cell and tissue stiffness is a critical biomechanical signal in biological processes.
- Current medical implants often have a mechanical mismatch with surrounding tissues.
- Responsive materials are needed for adaptable and functional in vivo implants.
Purpose of the Study:
- To develop thermoresponsive poly(urea-urethane) nanohybrid scaffolds with 'stiffness memory'.
- To utilize a 3D printing-guided thermally induced phase separation (3D-TIPS) technique for scaffold fabrication.
- To create scaffolds with tunable mechanical properties and complex geometries for soft tissue applications.
Main Methods:
- Developed a 3D printing-guided thermally induced phase separation (3D-TIPS) technique.
- Fabricated thermoresponsive poly(urea-urethane) nanohybrid scaffolds with interconnected pores.
- Investigated scaffold properties including hyperelasticity, porosity, crystallinity, and stiffness relaxation.
Main Results:
- Successfully manufactured scaffolds with tunable stiffness, controlled porosity, and complex anatomical geometries.
- Demonstrated 'stiffness memory' in scaffolds, attributed to semi-crystalline polymeric reverse self-assembly.
- Observed gradual stiffness relaxation during in vitro cell culture with minimal shape change, promoting human fibroblast growth.
Conclusions:
- The 3D-TIPS technique enables the creation of advanced nanohybrid elastomer scaffolds with unique properties.
- Scaffolds exhibit 'stiffness memory' and gradual softening, offering a better mechanical match to host tissues.
- These findings hold promise for developing personalized, biologically responsive soft tissue implants.
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