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Abstract Direct laser writing (DLW) via two‐photon polymerization is an emerging highly precise technique for the fabrication of intricate cellular scaffolds. Despite recent progress in using two‐photon‐polymerized scaffolds to probe fundamental cell behaviors, new methods to direct and modulate microscale cell alignment and selective cell adhesion using two‐photon‐polymerized microstructures are of keen interest. Here, a DLW‐fabricated 2D and 3D hydrogel microstructures, with alternating soft and stiff regions, for precisely controlled cell alignment are reported. The use of both cell‐adhesive and cell‐repellent hydrogels allows selective adhesion and alignment of human mesenchymal stem cells within the printed structure. Importantly, DLW patterning enables cell alignment on flat surfaces as well as irregular and curved 3D microstructures, which are otherwise challenging to pattern with cells.
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Enhanced adhesion in two-photon polymerization direct laser writing
We have quantified the adhesion forces between two-photon polymerization direct laser writing (TPP-DLW) microstructures and glass surfaces with and without an adhesion promoter. Glass surfaces treated with an acryloxy-silane agent produce adhesion forces that are almost three times larger than the forces observed with pristine glass surfaces. Determination of the substrates’ surface free energies suggests that the observed adhesion enhancement is chemical in its nature, implying that covalent bonds are formed between the polymer and the glass by means of the silane agent. The importance of this finding is demonstrated in the successful production of glassy carbon microstructures using TPP-DLW, followed by pyrolysis.
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- Award ID(s):
- 1905582
- PAR ID:
- 10597388
- Publisher / Repository:
- American Institute of Physics
- Date Published:
- Journal Name:
- AIP Advances
- Volume:
- 10
- Issue:
- 4
- ISSN:
- 2158-3226
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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