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This content will become publicly available on April 10, 2026

Title: 3D printing of low-cost, high-resolution open capillary microfluidics towards self-sustaining, long-term hydration of engineered living materials
Engineered living materials (ELMs) are an emerging class of biohybrid materials that have shown great promise with advanced capabilities unachievable by conventional materials. However, application of ELMs outside of the laboratory has been limited due to the need for periodic media replenishment or complete media immersion. We herein demonstrated the integration of capillary microfluidics for the autonomous and pump-free hydration of ELM hydrogels. We optimized 3D printing parameters, including exposure time and build plate lift and retract distances, to obtain microchannel dimensions capable of spontaneous capillary flow using a low-cost liquid crystal display stereolithographic apparatus (LCD-SLA) 3D printer and two hydrogel resins that are suitable for ELMs. Microchannel dimensions were accurate with ≤ 10% deviation between designed and measured widths and precise with coefficients of variation (CVs) <5% for microchannels ≥ 206.4 µm. We demonstrated proof-of-concept spontaneous capillary flow in 3D printed microfluidic devices using dye-incorporated lysogeny broth (LB). Snapshots of the devices captured up to 24 hours showed the diffusion of dye-incorporated LB throughout the bulk material. Through this proof-of-concept study, we have showcased the feasibility of integrating capillary microfluidics with ELMs for the autonomous and pump-free flow of fluids towards self-sustaining and long-term hydration.  more » « less
Award ID(s):
2223537
PAR ID:
10629251
Author(s) / Creator(s):
; ; ; ; ; ; ;
Publisher / Repository:
Springer
Date Published:
Journal Name:
Progress in Additive Manufacturing
ISSN:
2363-9512
Subject(s) / Keyword(s):
Engineered living materials Capillary microfluidics LCD-SLA 3D printing Stereolithography Hydrogel
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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