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Title: Solute Transport in Engineered Living Materials Using Bone‐Inspired Microscale Channel Networks
Engineered living materials (ELMs) are an emerging class of materials that are synthesized and/or populated by living cells to achieve novel functionalities including self‐healing and sensing. Providing nutrients to living cells within an ELM over prolonged periods remains a major technical challenge that limits the service life of ELMs. Bone maintains living cells for decades by delivering nutrients through a network of nanoscale channels punctuated by microscale pores. Nutrient transfer in bone is enabled by mechanical loading experienced by the material during regular use. Herein, the geometric traits of the network of channels and pores that can be used in ELMs to allow mechanical loading to enable nutrient delivery to resident cell populations are identified in a manner seen in bone. Transport occurs when deformation in the microscale pore network exceeds the volume of the connecting channels. Computational models show that transport is enhanced at greater loading magnitudes and lower loading frequencies. The computational results are confirmed using experiments with microfluidic systems. In the findings, quantitative design principles are provided for channel‐pore networks capable of sustained delivery of nutrients to living cells within materials.  more » « less
Award ID(s):
2342239 2135586 2055214
PAR ID:
10481835
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Engineering Materials
Volume:
25
Issue:
24
ISSN:
1438-1656
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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