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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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Airbrushed nanofibrous membranes to control stem cell infiltration in 3D ‐printed scaffolds
Abstract Extrusion‐based 3D printing of polymeric biomaterials has emerged as a promising approach for the fabrication of complex tissue engineering constructs. However, the large pore and feature size lead to low cell seeding efficiency and limited control of spatial distribution of cells within the scaffolds. We developed hybrid scaffolds that are composed of 3D‐printed layers and airbrushed fibrous membranes. Airbrushing time was adjusted to fabricate low (L), medium (M), and high (H) density membranes to effectively control stem cell infiltration. When two distinct populations of stem cells were seeded from top or bottom of the scaffolds, scaffolds composed ofLLLmembranes showed gradual mixing of the cells with depth, whereasLHLmembranes led to two distinct regions of cells separated by theHmembrane. Our results demonstrate that fibrous membranes incorporated within 3D‐printed layers enable user‐defined and spatially controlled cell compositions within hybrid scaffolds.
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- Award ID(s):
- 2044479
- PAR ID:
- 10360466
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- AIChE Journal
- Volume:
- 67
- Issue:
- 12
- ISSN:
- 0001-1541
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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