Final published version
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Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
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TY - JOUR
T1 - Reversible Trapping of Colloids in Microgrooved Channels via Diffusiophoresis under Steady-State Solute Gradients
AU - Singh, Naval
AU - Vladisavljević, Goran T.
AU - Nadal, François
AU - Cottin-Bizonne, Cécile
AU - Pirat, Christophe
AU - Bolognesi, Guido
PY - 2020/12/11
Y1 - 2020/12/11
N2 - The controlled transport of colloids in dead-end structures is a key capability that can enable a wide range of applications, such as biochemical 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 submicron particles within dead-end microgrooves 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.
AB - The controlled transport of colloids in dead-end structures is a key capability that can enable a wide range of applications, such as biochemical 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 submicron particles within dead-end microgrooves 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.
U2 - 10.1103/PhysRevLett.125.248002
DO - 10.1103/PhysRevLett.125.248002
M3 - Journal article
VL - 125
JO - Physical review letters
JF - Physical review letters
SN - 1079-7114
IS - 24
M1 - 248002
ER -