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Aluminum nanoparticles as substrates for metal-enhanced fluorescence in the ultraviolet for the label-free detection of biomolecules.

ABSTRACT: We use finite-difference time-domain calculations to show that aluminum nanoparticles are efficient substrates for metal-enhanced fluorescence (MEF) in the ultraviolet (UV) for the label-free detection of biomolecules. The radiated power enhancement of the fluorophores in proximity to aluminum nanoparticles is strongly dependent on the nanoparticle size, fluorophore-nanoparticle spacing, and fluorophore orientation. Additionally, the enhancement is dramatically increased when the fluorophore is between two aluminum nanoparticles of a dimer. Finally, we present experimental evidence that functionalized forms of amino acids tryptophan and tyrosine exhibit MEF when spin-coated onto aluminum nanostructures.

SUBMITTER: Chowdhury MH

PROVIDER: S-EPMC2729167 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Aluminum nanoparticles as substrates for metal-enhanced fluorescence in the ultraviolet for the label-free detection of biomolecules.

Chowdhury Mustafa H MH Ray Krishanu K Gray Stephen K SK Pond James J Lakowicz Joseph R JR

Analytical chemistry 20090201 4

We use finite-difference time-domain calculations to show that aluminum nanoparticles are efficient substrates for metal-enhanced fluorescence (MEF) in the ultraviolet (UV) for the label-free detection of biomolecules. The radiated power enhancement of the fluorophores in proximity to aluminum nanoparticles is strongly dependent on the nanoparticle size, fluorophore-nanoparticle spacing, and fluorophore orientation. Additionally, the enhancement is dramatically increased when the fluorophore is ...[more]

PMID: 19159327

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