posted on 2020-11-04, 07:17authored byEkrem Ozkan, Arnab Mondal, Priyadarshini Singha, Megan Douglass, Sean P. Hopkins, Ryan Devine, Mark Garren, James Manuel, James Warnock, Hitesh Handa
Biofilm
and thrombus formation on surfaces results in significant
morbidity and mortality worldwide, which highlights the importance
of the development of efficacious fouling-prevention approaches. In
this work, novel highly robust and superhydrophobic coatings with
outstanding multiliquid repellency, bactericidal performance, and
extremely low bacterial and blood adhesion are fabricated by a simple
two-step dip-coating method. The coatings are prepared combining 1H,1H,2H,2H-perfluorooctyltriethoxysilane (FAS-17)-coated hydrophobic zinc oxide
and copper nanoparticles to construct hierarchical micro/nanostructures
on commercial polyurethane (PU) sponges followed by polydimethylsiloxane
(PDMS) treatment that is used to improve the binding degree between
the nanoparticles and the sponge surface. The micro/nanotextured samples
can repel various liquids including water, milk, coffee, juice, and
blood. Relative to the original PU, the superhydrophobic characteristics
of the fabricated sponge cause a significant reduction in the adhesion
of bacteria (Staphylococcus aureus)
by up to 99.9% over a 4-day period in a continuous drip-flow bioreactor.
The sponge is also highly resistant to the adhesion of fibrinogen
and activated platelets with ∼76 and 64% reduction, respectively,
hence reducing the risk of blood coagulation and thrombus formation.
More importantly, the sponge can sustain its superhydrophobicity even
after being subjected to different types of harsh mechanical damage
such as finger-wiping, knife-scratching, tape-peeling, hand-kneading,
hand-rubbing, bending, compress–release (1000 cycles) tests,
and 1000 cm sandpaper abrasion under 250 g of loading. Hence, this
novel hybrid surface with robustness and the ability to resist blood
adhesion and bacterial contamination makes it an attractive candidate
for use in diverse application areas.