la9b03546_si_001.pdf (228.4 kB)
Controlling the Spatiotemporal Transport of Particles in Fluid-Filled Microchambers
journal contribution
posted on 2020-02-28, 21:33 authored by Abhrajit Laskar, Oleg E. Shklyaev, Anna C. BalazsThe development of microscale devices
that autonomously perform
multistep processes is vital to advancing the use of microfluidics
in industrial applications. Such advances can potentially be achieved
through the use of “chemical pumps” that transduce the
energy from inherent catalytic reactions into fluid flow within microchambers,
without the need for extraneous external equipment. Using computational
modeling, we focus on arrangements of multiple chemical pumps that
are formed by anchoring patches of different enzymes onto the floor
of a fluid-filled chamber. With the addition of the appropriate reactants,
only one of the enzymatic patches is activated and thereby generates
fluid flow centered about that patch. These flows drive the self-assembly
of microparticles in the solution and localize the particles onto
the activated patches. By varying the spatial arrangement of the enzymatic
patches, and the sequence in which the appropriate reactants are added
to the solution, we realize spatiotemporal control over the fluid
flow and the sequential transport of microparticles from one patch
to another. The order in which the particles visit the different patches
can be altered by varying the sequence in which the reactants are
added to the solution. By harnessing catalytic cascade reactions,
where the product of one reaction is the reactant for the next, we
achieve directed transport between the patches with the addition of
just one reactant, which initiates the catalytic cascade. Through
these studies, we show how the trajectory of the particles’
motion among different “stations” can be readily regulated
through intrinsic catalytic reactions and thus, provide guidelines
for creating fluidic devices that perform multistep reactions in an
autonomous, self-sustained manner.