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Generating stable and customizable topography on hydrogel surfaces with contact guidance potential is critical as it can direct/influence cell growth. This necessitates the development of new techniques for surface patterning of the hydrogels. We report on the design of a square grid template for surface patterning hydrogels. The template was 3-D printed and has the diameter of a well in a 24-well plate. Hyaluronic acid methacrylate (HA) hydrogel precursor solutions were cast on the 3D printed template’s surface, which generated 3D square shape topographies on the HA hydrogel surface upon demolding. The 3D Laser Microscopy has shown the formation of a periodic array of 3D topographies on hydrogel surfaces. 3D Laser and Electron Microscopy Imaging have revealed that this new method has increased the surface area and exposed the underlying pore structure of the HA hydrogels. To demonstrate the method’s versatility, we have successfully applied this technique to generate 3D topography on two more acrylate hydrogel formulations, gelatin Methacrylate and polyethylene glycol dimethacrylate. Human neonatal dermal fibroblast cells were used as a model cell line to evaluate the cell guidance potential of patterned HA hydrogel. Confocal fluorescence microscopy imaging has revealed that the 3D surface topographies on HA hydrogels can guide and align the actin filaments of the fibroblasts presumably due to the contact guidance mechanism. The newly developed methodology of 3D topography generation in acrylate hydrogels may influence the cell responses on hydrogel surfaces which can impact biomedical applications such as tissue engineering, wound healing, and disease modeling.
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Nanoscale 3D printing of hydrogels for cellular tissue engineering
Hydrogel scaffolds that mimic the native extracellular matrix (ECM) environment play a crucial role in tissue engineering. It has been demonstrated that cell behaviors can be affected by not only the hydrogel's physical and chemical properties, but also its three dimensional (3D) geometrical structures. In order to study the influence of 3D geometrical cues on cell behaviors as well as the maturation and function of engineered tissues, it is imperative to develop 3D fabrication techniques for creating micro and nanoscale hydrogel constructs. Among existing techniques that can effectively pattern hydrogels, two-photon polymerization (2PP)-based femtosecond laser 3D printing technology allows one to produce hydrogel structures with a resolution of 100 nm. This article reviews the basics of this technique and some of its applications in tissue engineering.
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- PAR ID:
- 10075796
- Date Published:
- Journal Name:
- Journal of Materials Chemistry B
- Volume:
- 6
- Issue:
- 15
- ISSN:
- 2050-750X
- Page Range / eLocation ID:
- 2187 to 2197
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/C8TB00301G
