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This content will become publicly available on December 1, 2025

Title: Collective buoyancy-driven dynamics in swarming enzymatic nanomotors
Enzymatic nanomotors harvest kinetic energy through the catalysis of chemical fuels. When a drop containing nanomotors is placed in a fuel-rich environment, they assemble into ordered groups and exhibit intriguing collective behaviour akin to the bioconvection of aerobic microorganismal suspensions. This collective behaviour presents numerous advantages compared to individual nanomotors, including expanded coverage and prolonged propulsion duration. However, the physical mechanisms underlying the collective motion have yet to be fully elucidated. Our study investigates the formation of enzymatic swarms using experimental analysis and computational modelling. We show that the directional movement of enzymatic nanomotor swarms is due to their solutal buoyancy. We investigate various factors that impact the movement of nanomotor swarms, such as particle concentration, fuel concentration, fuel viscosity, and vertical confinement. We examine the effects of these factors on swarm self-organization to gain a deeper understanding. In addition, the urease catalysis reaction produces ammonia and carbon dioxide, accelerating the directional movement of active swarms in urea compared with passive ones in the same conditions. The numerical analysis agrees with the experimental findings. Our findings are crucial for the potential biomedical applications of enzymatic nanomotor swarms, ranging from enhanced diffusion in bio-fluids and targeted delivery to cancer therapy.  more » « less
Award ID(s):
2140010
PAR ID:
10640438
Author(s) / Creator(s):
; ; ; ; ;
Corporate Creator(s):
Editor(s):
NA
Publisher / Repository:
Springer
Date Published:
Journal Name:
Nature Communications
Volume:
15
Issue:
1
ISSN:
2041-1723
Subject(s) / Keyword(s):
swarming, collective motion, enzyme self-organization
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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