8 research outputs found
Schutzhelme fuer motorisierte Zweiradfahrer Band 1: Laboruntersuchungen
TIB: RN 6741 (91) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman
High Aspect Ratio Nanostructures Kill Bacteria <i>via</i> Storage and Release of Mechanical Energy
The
threat of a global rise in the number of untreatable infections
caused by antibiotic-resistant bacteria calls for the design and fabrication
of a new generation of bactericidal materials. Here, we report a concept
for the design of antibacterial surfaces, whereby cell death results
from the ability of the nanofeatures to deflect when in contact with
attaching cells. We show, using three-dimensional transmission electron
microscopy, that the exceptionally high aspect ratio (100–3000)
of vertically aligned carbon nanotubes (VACNTs) imparts extreme flexibility,
which enhances the elastic energy storage in CNTs as they bend in
contact with bacteria. Our experimental and theoretical analyses demonstrate
that, for high aspect ratio structures, the bending energy stored
in the CNTs is a substantial factor for the physical rupturing of
both Gram-positive and Gram-negative bacteria. The highest bactericidal
rates (99.3% for <i>Pseudomonas aeruginosa</i> and 84.9%
for <i>Staphylococcus aureus</i>) were obtained by modifying
the length of the VACNTs, allowing us to identify the optimal substratum
properties to kill different types of bacteria efficiently. This work
highlights that the bactericidal activity of high aspect ratio nanofeatures
can outperform both natural bactericidal surfaces and other synthetic
nanostructured multifunctional surfaces reported in previous studies.
The present systems exhibit the highest bactericidal activity of a
CNT-based substratum against a Gram-negative bacterium reported to
date, suggesting the possibility of achieving close to 100% bacterial
inactivation on VACNT-based substrata
Schutzhelme fuer motorisierte Zweiradfahrer Band 4: Helmvisiere. Teil 1.2. Bericht zu den Forschungsprojekten 7807/2 u. 3
TIB: RN 6741 (150) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman