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Title: Aspiration-assisted bioprinting for precise positioning of biologics
Three-dimensional (3D) bioprinting is an appealing approach for building tissues; however, bioprinting of mini-tissue blocks (i.e., spheroids) with precise control on their positioning in 3D space has been a major obstacle. Here, we unveil “aspiration-assisted bioprinting (AAB),” which enables picking and bioprinting biologics in 3D through harnessing the power of aspiration forces, and when coupled with microvalve bioprinting, it facilitated different biofabrication schemes including scaffold-based or scaffold-free bioprinting at an unprecedented placement precision, ~11% with respect to the spheroid size. We studied the underlying physical mechanism of AAB to understand interactions between aspirated viscoelastic spheroids and physical governing forces during aspiration and bioprinting. We bioprinted a wide range of biologics with dimensions in an order-of-magnitude range including tissue spheroids (80 to 600 μm), tissue strands (~800 μm), or single cells (electrocytes, ~400 μm), and as applications, we illustrated the patterning of angiogenic sprouting spheroids and self-assembly of osteogenic spheroids.  more » « less
Award ID(s):
1914885 1735627
NSF-PAR ID:
10179828
Author(s) / Creator(s):
; ; ; ; ; ;
Date Published:
Journal Name:
Science Advances
Volume:
6
Issue:
10
ISSN:
2375-2548
Page Range / eLocation ID:
eaaw5111
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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