Abstract

We combine two-photon lithography and optical tweezers to investigate the Brownian fluctuations and propeller characteristics of a microfabricated helix. From the analysis of mean squared displacements and time correlation functions we recover the components of the full mobility tensor. We find that Brownian motion displays correlations between angular and translational fluctuations from which we can directly measure the hydrodynamic coupling coefficient that is responsible for thrust generation. By varying the distance of the microhelices from a no-slip boundary we can systematically measure the effects of a nearby wall on the resistance matrix. Our results indicate that a rotated helix moves faster when a nearby no-slip boundary is present, providing a quantitative insight on thrust enhancement in confined geometries for both synthetic and biological microswimmers.

Details

Title
Brownian fluctuations and hydrodynamics of a microhelix near a solid wall
Author
Bianchi Silvio 1 ; Carmona Sosa Viridiana 2 ; Gaszton, Vizsnyiczai 3 ; Di, Leonardo Roberto 2 

 NANOTEC-CNR, Institute of Nanotechnology, Soft and Living Matter Laboratory, Roma, Italy 
 University of Rome “Sapienza”, Physics Department, Roma, Italy (GRID:grid.7841.a) 
 University of Rome “Sapienza”, Physics Department, Roma, Italy (GRID:grid.7841.a); Biological Research Centre, Institute of Biophysics, Szeged, Hungary (GRID:grid.418331.c) (ISNI:0000 0001 2195 9606) 
Publication year
2020
Publication date
2020
Publisher
Nature Publishing Group
e-ISSN
20452322
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2376711762
Copyright
This work is published under http://creativecommons.org/licenses/by/4.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.