Fabrication of Slippery Liquid-Infused Coatings in Flexible Narrow-Bore Tubing

We
report a layer-by-layer suction-and-flow approach that enables
the fabrication of polymer-based “slippery” liquid-infused
porous surfaces (SLIPS) in the confined luminal spaces of flexible,
narrow-bore tubing. These SLIPS-coated tubes can prevent or strongly
reduce surface fouling after prolonged contact, storage, or flow of
a broad range of complex fluids and viscoelastic materials, including
many that are relevant in the contexts of medical devices (e.g., blood
and urine), food processing (beverages and fluids), and other commercial
and industrial applications. The robust and mechanically compliant
nature of the nanoporous coating used to host the lubricating oil
phase allows these coated tubes to be bent, flexed, and coiled repeatedly
without affecting their inherent slippery and antifouling behaviors.
Our results also show that SLIPS-coated tubes can prevent the formation
of bacterial biofilms after prolonged and repeated flow-based exposure
to the human pathogen Staphylococcus aureus and that the anti-biofouling properties of these coated tubes can
be further improved or prolonged by coupling this approach with strategies
that permit the sustained release of broad-spectrum antimicrobial
agents. The suction-and-flow approach used here enables the application
of slippery coatings in the confined luminal spaces of narrow-bore
tubing that are difficult to access using several other methods for
the fabrication of liquid-infused coatings and can be applied to tubing
of arbitrary length and diameter. We anticipate that the materials
and approaches reported here will prove useful for reducing or preventing
biofouling, process fouling, and the clogging or occlusion of tubing
in a wide range of consumer, industrial, and healthcare-oriented applications.