Anti-Biofouling and Self-Cleaning Surfaces Featured with Magnetic Artificial Cilia

The fouling of surfaces
submerged in a liquid is a serious problem
for many applications including lab-on-a-chip devices and marine sensors.
Inspired by the versatility of cilia in manipulating fluids and particles,
it is experimentally demonstrated that surfaces partially covered
with magnetic artificial cilia (MAC) have the capacity to efficiently
prevent attachment and adhesion of real biofouling agentsmicroalgae Scenedesmus sp. Actuation of the MAC resulted in
over 99% removal of the algae for two different scenarios: (1) actuating
the MAC immediately after injecting the algae into a microfluidic
chip, demonstrating antifouling and (2) starting to actuate the MAC
1 week after injecting the algae into the chip and leaving them to
grow in static conditions, showing self-cleaning. It is shown that
the local and global flows generated by the actuated MAC are substantial,
resulting in hydrodynamic shear forces acting on the algae, which
are likely to be key to efficient antifouling and self-cleaning. These
findings and insights will potentially lead to novel types of self-cleaning
and antifouling strategies, which may have a relevant practical impact
on different fields and applications including lab-on-a-chip devices
and water quality analyzers.