3D structures with complex geometric features at the microscale, such as microparticles and microfibers, have promising applications in biomedical engineering, self‐assembly, and photonics. Fabrication of complex 3D microshapes at scale poses a unique challenge; high‐resolution methods such as two‐photon‐polymerization have print speeds too low for high‐throughput production, while top‐down approaches for bulk processing using microfabricated template molds have limited control of microstructure geometries over multiple axes. Here, a method for microshape fabrication is presented that combines a thermally drawn transparent fiber template with a masked UV‐photopolymerization approach to enable biaxial control of microshape fabrication. Using this approach, high‐resolution production of complex microshapes not producible using alternative methods is demonstrated, such as octahedrons, dreidels, and axially asymmetric fibers, at throughputs as high as 825 structures/minute. Finally, the fiber template is functionalized with conductive electrodes to enable hierarchical subparticle localization using dielectrophoretic forces.
The controllable production of microparticles with complex geometries is useful for a variety of applications in materials science and bioengineering. The formation of intricate microarchitectures typically requires sophisticated fabrication techniques such as flow lithography or multiple-emulsion microfluidics. By harnessing the molecular interactions of a set of artificial intrinsically disordered proteins (IDPs), we have created complex microparticle geometries, including porous particles, core-shell and hollow shell structures, and a unique ‘fruits-on-a-vine’ arrangement, by exploiting the metastable region of the phase diagram of thermally responsive IDPs within microdroplets. Through multi-site unnatural amino acid (UAA) incorporation, these protein microparticles can also be photo-crosslinked and stably extracted to an all-aqueous environment. This work expands the functional utility of artificial IDPs as well as the available microarchitectures of this class of biocompatible IDPs, with potential applications in drug delivery and tissue engineering.
more » « less- NSF-PAR ID:
- 10153552
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 11
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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