Black silicon spacing effect on bactericidal efficacy against gram-positive bacteria

Abstract

The morphology of regular and uniform arrays of black silicon structures were evaluated for bactericidal efficacy 
against gram-positive, nonmotile \textit{Staphylococcus~epidermidis} (\textit{S.~epidermidis}). 
In this study, uniform and regular arrays of black silicon structures were fabricated using nanosphere lithography. A systematic evaluation of nanomorphology effects on bacterial killing were studied with 300 to 1400 nm pitch 
silicon nanostructures
on spherical cocci of about 500 to 1000 nm in diameter. Our results show that morphology factors such as height and roughness do not directly determine bactericidal efficacy. Instead, the spacing between nanostructures is key in determining how bacteria are stretched and lysed. 
Smaller pitch nanostructures are better for killing bacteria and an 
$82 \pm 3$ $\%$ enhancement in the killing was observed for 300 nm pitch nanoneedles surface compared to the flat control substrates.

Flexible Embedded Metal Meshes by Sputter-Free Crack Lithography for Transparent Electrodes and Electromagnetic Interference Shielding

“…We transferred the self-forming cracks to the PET using RIE with a gas flow of 50 sccm CF 4 and 20 sccm SF 6 , a pressure of 30 mT, and a power of 250 W. RIE is well-suited for etching high-aspect-ratio anisotropic structures, such as deep trenches or narrow channels. This capability is essential for creating complex patterns with varying depths. , RIE provides control over the etch rate, resulting in varying trench thicknesses. , However, it is important to note that the crack template layer is also susceptible to etching. This imposes a limitation on the maximum etching time and, consequently, the achievable depth of the trenches.…”

“…This capability is essential for creating complex patterns with varying depths. 42 , 75 RIE provides control over the etch rate, resulting in varying trench thicknesses. 42 , 43 However, it is important to note that the crack template layer is also susceptible to etching.…”

Multi-BOWS: multi-fidelity multi-objective Bayesian optimization with warm starts for nanophotonic structure design

“…34–37 It is noteworthy that these nanocone structures could be fabricated by maskless reactive ion etching 5,6,38 or nanosphere lithography combined with etching. 39 However, designing nanocone structures introduce the need to optimize over many parameters, necessitating a large number of structure evaluations.…”

Bactericidal Performance of Nanostructures Resin Surfaces: Nanopillars versus Nanocones

“…These findings diverge from the expected pattern of nanopillar spacing's influence on bactericidal properties and contradict prior literatures. 30,31 3.3. Local Elastic Modulus to Bactericidal Performance.…”