Light‐Enhancing Plasmonic‐Nanopore Biosensor for Superior Single‐Molecule Detection

Abstract

A stacked plasmonic nanowell-nanopore biosensor strongly suppresses the background fluorescence from the bulk and yields net more than tenfold enhancement of the fluorescence intensity. The device offers extremely high signal-to-background (S/B) ratio for single-molecule detection at ultralow excitation laser intensities, while maintaining extremely high temporal bandwidth for single-DNA sensing.

Surface coatings for solid-state nanopores

“…In the past two decades, nanopore-based analysis of single biomolecules or nanoparticles has undergone rapid development for the detection and characterization of DNA, proteins, viruses and synthetic nanoparticles. [1][2][3][4][5][6][7][8][9][10][11][12][13] Recent advancements include the development of the portable MinION device for DNA sequencing with protein nanopores, 14,15 the combination of nanopore recordings with additional modalities for sensing, characterizing, or manipulating molecules such as detecting fluorescent molecules based on plasmonic effects, [16][17][18][19][20][21][22] recording changes in the local voltage of a graphene nanoribbon transistor, 23 or pulling on or holding molecules in a nanopore with optical tweezers. 24,25 In most cases, the basic experimental setup to detect and characterize single molecules in nanopores comprises two compartments of electrolyte solution, a thin insulating membrane that separates these compartments, and a single pore with a diameter ranging from 1-50 nm that constitutes the only connection between the two compartments ( Fig.…”

Exploration of solid-state nanopores in characterizing reaction mixtures generated from a catalytic DNA assembly circuit

“…Increasing efforts are being made to solve this problem, e.g. adjusting the nanopore geometry, 66,67 using two-dimensional materials, 68 building DNA origami nanopores, [69][70][71] chemical modication, 49,50,[72][73][74][75][76][77] etc. Imperative data processing 78,79 and novel strategies in which dynamic ionic ow was used instead of a classic "metal wire" have also been developed to realize the high resolution analysis of signal redox molecules, cells and nanoparticle mixtures.…”

Hybrid plasmonic nanostructures based on controlled integration of MoS2 flakes on metallic nanoholes

“…This result suggests a possible means to switch the system based on this effect. For example, this switching could be interesting for applications where single molecules pass through the pore for sensing based on enhanced spectroscopy, such as SERS or metal enhanced fluorescence (MEF) 14,15 , both of which are now of great interest for sequencing applications. From the perspective of the fabrication point, as is well known, a single layer of MoS2 is approximately 0.7 nm thick, and a nanopore can be easily prepared by means of focused electron beam exposure (using TEM) 4,5 .…”