Janus porous biomaterials are gaining increasing attention and there are considerable efforts to develop simple, rapid, and scalable methods capable of tuning micro‐ and macro‐structures. Here, a single‐step electro‐fabrication method to create a Janus porous film by the electrodeposition of the amino‐polysaccharide chitosan is reported. Specifically, a Janus structure emerges spontaneously when electrodeposition is performed at sub‐ambient temperature (0–5 °C). Sub‐ambient temperature electrodeposition experiments show that: a Janus microstructure emerges (potentially as the result of a subtle alteration of the intermolecular interactions responsible for self‐assembly); important microstructural features (pore size, porosity, and thicknesses) can be tuned by conditions; and this method is readily scalable (vs serial printing) and can yield complex tubular structures with Janus faces. In vitro studies demonstrate anisotropic cell guidance, and in vivo studies using a rat calvarial defect model further confirm the beneficial features of such Janus porous film for guided bone regeneration. In summary, these results further demonstrate that electro‐fabrication provides a simple and scalable platform technology for the controlled functional structures of soft matter for applications in regenerative medicine.
Janus films with controlled pore structures can be particularly important in diverse applications. There remains a challenge for simple, rapid, and scalable fabrication methods to control Janus balance (JB) including the thickness of the individual face as well as porosity and pore size. Here the electrofabrication of a porous Janus film with controlled Janus balance from aminopolysaccharide chitosan under the salt effect is reported. Sequential deposition of chitosan under programmable salt environment and electrochemical conditions enables construction of Janus films with precisely controlled Janus balance. Bioactive partially soluble calcium phosphate (CaP) salts can also generate porous structure in Janus film. It is specifically reported that a chitosan/hydroxyl apatite (HAp) composite Janus film can serve as an effective scaffold for guided bone regeneration. The dense layer functions to provide mechanical support and serves as a barrier for fibrous connective tissue penetration. The porous composite layer functions to provide the microenvironment for osteogenesis. In vivo studies using a rat calvarial defect model confirm the beneficial features of this Janus composite for guided bone regeneration. These results suggest the potential of electrofabrication as a simple and scalable platform technology to tune the self‐organization of soft matter for a range of emerging applications.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Functional Materials
- Medium: X
- Sponsoring Org:
- National Science Foundation
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