Plasmonic Nanocavity Metasurface Based on Laser-Structured Silver Surface and Silver Nanoprisms for the Enhancement of Adenosine Nucleotide Photoluminescence

Abstract

A reliable photoluminescence (PL) spectroscopy and imaging of biomolecules at room temperature is a challenging and important problem of biophysics, biochemistry, and molecular genetics. A unique effect of strong plasmonic enhancement of the PL by metal nanostructures is one of the most effective approaches for this purpose. The highest enhancement is provided by metal nanostructures with densely packed sharp tips, periodically arranged metal nanostructures, and plasmonic cavities. All of these features have been realized in the plasmonic cavity metasurface based on the silver (Ag) laser-induced periodic surface structure and Ag triangular nanoprisms studied in the present work. The strong plasmon-enhanced PL of 5′-deoxyadenosine monophosphate deposited on such metasurfaces has been revealed at room temperature. The observed enhancement of more than 1000-fold has been interpreted as a result of synergetic action of the generation of a high concentration of hot spots near the sharp edges of the laser-induced surface structure and nanoprisms together with excitation of the collective gap mode of the cavity due to strong near-field plasmonic coupling. Correspondingly, the plasmonic cavity metasurfaces consisting of metal laser-induced periodic surface structures and nonspherical metal nanoparticles with sharp edges have been shown to be crucial for the highly sensitive detection and imaging of biomolecules at room temperature without consuming any dye labels.

Enhancement of Raman Scattering and Exciton/Trion Photoluminescence of Monolayer and Few-Layer MoS2 by Ag Nanoprisms and Nanoparticles: Shape and Size Effects

“…77 Such a strong enhancement is caused by the generation of a very intense local plasmonic EM field near the edges and tips of nonspherical NPs (so-called hot spots). 78 Ag nanotriangles (NTs or nanoprisms) are nonspherical metal NPs that can be successfully used for this scope. For example, recently, Chan et al 79 coated Ag NTs on the surface of 2D MoS 2 and observed a large enhancement in transient reflectivity and also verified an increase in the absorption due to local surface-plasmoninduced near-field enhancement.…”

“…An enhancement of more than an order of magnitude was reported for Raman scattering and PL intensity in ML MoS 2 integrated with the Ag bowtie array compared to bare MoS 2 . Such a strong enhancement is caused by the generation of a very intense local plasmonic EM field near the edges and tips of nonspherical NPs (so-called hot spots) . Ag nanotriangles (NTs or nanoprisms) are nonspherical metal NPs that can be successfully used for this scope.…”

“…NTs are already being used for photovoltaics, biomedical, biosensing, , and surface-enhanced Raman scattering (SERS) applications. The success in the use of nanoprisms comes from their good SPR from the edges of the triangle, providing large local field enhancement .…”

“…NTs are already being used for photovoltaics, biomedical, biosensing, , and surface-enhanced Raman scattering (SERS) applications. The success in the use of nanoprisms comes from their good SPR from the edges of the triangle, providing large local field enhancement . Despite their potential, very few papers have reported the plasmonic enhancement of 2D materials, in particular MoS 2 , using Ag NTs, and to the best of our knowledge, to date, no one has worked on PL and Raman enhancement by plasmonic effects of Ag NTs with MoS 2 .…”

Laser-Induced Periodic Ag Surface Structure with Au Nanorods Plasmonic Nanocavity Metasurface for Strong Enhancement of Adenosine Nucleotide Label-Free Photoluminescence Imaging

“…42−47 The application of LIPSS for the formation of plasmonic cavity may be promising due to the ability of biomolecules to bind to the edges of nanostructures, which leads to a stronger plasmonic enhancement. 15,41,48,49 The structures of such metal− dielectric cavities possess the advantages of both metal and dielectric materials. Indeed, metal NPs highly support subwavelength plasmons with a strong local EM field; however, they are characterized by relatively high intrinsic material losses.…”