.
We tested
the properties of diffusion in microfluidics labyrinths,
explored the impact of confinement
on diffusion : can it create anomalous diffusion; would
it be enhanced or in contrast hindered ?
The purpose of this study is twofold. Using microfluidic networks and
our system of fringe pattern photobleaching, we studied the diffusion of
particles at two levels: inside the elementary cells, and at a macroscopic
level (up to 100 cells
We investigated the probability of escape from a cell, and then the
possibility of anomalous, enhanced diffusion, while the elementary step is
fixed.
The characteristic dimension of the cells is about 50 µm; we vary the
size and the number of connections between these elementary cells to create
anistropic labyrinths (mimicking the micelles in the Levy flight process) or
symmetric situations (picture).
The particles are “trapped and released”, from cell to cell, mimicking
the “corral and fence” hypothesis of real membranes.
We found that the particles follow an enhanced diffusion at the scale of
one to three cells, but their macroscopic movement rapidly finds back its
Brownian character.
|