1 research outputs found
Nanopatterned Smart Polymer Surfaces for Controlled Attachment, Killing, and Release of Bacteria
Model
surfaces with switchable functionality based on nanopatterned,
thermoresponsive poly(<i>N</i>-isopropylacrylamide) (PNIPAAm)
brushes were fabricated using interferometric lithography combined
with surface-initiated polymerization. The temperature-triggered hydration
and conformational changes of nanopatterned PNIPAAm brushes reversibly
modulate the spatial concealment and exposure of molecules that are
immobilized in the intervals between nanopatterned brushes. A biocidal
quaternary ammonium salt (QAS) was used to demonstrate the utility
of nanopatterned PNIPAAm brushes to control biointerfacial interactions
with bacteria. QAS was integrated into polymer-free regions of the
substrate between nanopatterned PNIPAAm brushes. The biocidal efficacy
and release properties of these surfaces were tested against <i>Escherichia coli</i> K12. Above the lower critical solution
temperature (LCST) of PNIPAAm, desolvated, collapsed polymer chains
facilitate the attachment of bacteria and expose QAS moieties that
kill attached bacteria. Upon a reduction of the temperature below
the LCST, swollen PNIPAAm chains promote the release of dead bacteria.
These results demonstrate that nanopatterned PNIPAAm/QAS hybrid surfaces
are model systems that exhibit an ability to undergo noncovalent,
dynamic, and reversible changes in structure that can be used to control
the attachment, killing, and release of bacteria in response to changes
in temperature