main_SI.pdf (664.63 kB)

Supplementary Information Files for Reversible trapping of colloids in microgrooved channels via diffusiophoresis under steady-state solute gradients

Download (664.63 kB)
dataset
posted on 23.11.2020, 11:13 by Naval Singh, Goran VladisavljevicGoran Vladisavljevic, Francois NadalFrancois Nadal, Cécile Cottin-Bizonne, Christophe Pirat, Guido BolognesiGuido Bolognesi
Supplementary Information Files for Reversible trapping of colloids in microgrooved channels via diffusiophoresis under steady-state solute gradients
The controlled transport of colloids in dead-end structures is a key capability that can enable a wide range of applications, such as bio-chemical analysis, drug delivery and underground oil recovery. This letter presents a new trapping mechanism that allows the fast (i.e., within a few minutes) and reversible accumulation of sub-micron particles within dead-end micro-grooves by means of parallel streams with different salinity level. For the first time, particle focusing in dead-end structures is achieved under steady-state gradients. Confocal microscopy analysis and numerical investigations show that the particles are trapped at a flow recirculation region within the grooves due to a combination of diffusiophoresis transport and hydrodynamic effects. Counterintuitively, the particle velocity at the focusing point is not vanishing and, hence, the particles are continuously transported in and out of the focusing point. The accumulation process is also reversible and one can cyclically trap and release the colloids by controlling the salt concentration of the streams via a flow switching valve.

Funding

Particle Filtration and Accumulation by Solute-driven Transport (FAST) for bio-analysis in microfluidic devices

Engineering and Physical Sciences Research Council

Find out more...

Tackling Antimicrobial Resistance: An Interdisciplinary Approach

Engineering and Physical Sciences Research Council

Find out more...

History

School

  • Aeronautical, Automotive, Chemical and Materials Engineering
  • Mechanical, Electrical and Manufacturing Engineering

Department

  • Chemical Engineering