English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Zendy Plus

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Zendy Tools

Zendy Open

Electromagnetic hot-spots at ultra-narrow plasmonic nanogaps carry immensepotential to drive detection limits down to few molecules in sensors based onsurface enhanced Raman or Fluorescence spectroscopies. However, leveraging theEM hot-spots requires access to the gaps, which in turn depends on the size ofthe analyte in relation to gap distances. Herein we leverage a well-calibratedprocess based on self-assembly of block copolymer colloids on full-wafer levelto produce high density plasmonic nanopillar arrays exhibiting large number (>10^10 /cm^2) of uniform inter-pillar EM hot-spots. The approach allowsconvenient handles to systematically vary the inter-pillar gap distances downto sub-10 nm regime. The results show compelling trends of the impact ofanalyte dimensions in relation to the gap distances towards their leverage overinter-pillar hot-spots, and the resulting sensitivity in SERS based molecularassays. Comparing the detection of labelled proteins in surface-enhanced Ramanand metal-enhanced Fluorescence configurations further reveal the relativeadvantage of Fluorescence over Raman detection while encountering the spatiallimitations imposed by the gaps. Quantitative assays with limits of detectiondown to picomolar concentrations is realized for both the small organicmolecules and the proteins. The well-defined geometries delivered bynanofabrication approach is critical to arriving at realistic geometric modelsto establish meaningful correlation between structure, optical properties andsensitivity of nanopillar arrays in plasmonic assays. The findings emphasizethe need for the rational design of EM hot-spots that take into account theanalyte dimensions to drive ultra-high sensitivity in plasmon-enhancedspectroscopies.

Investigating Analyte Co-Localization at Electromagnetic Gap Hot-Spots  For Highly Sensitive (Bio)molecular Detection by Plasmon Enhanced  Spectroscopies