DNA Translocations through Solid-State Plasmonic Nanopores

• Published in: Nano letters 2014-12, Vol.14 (12), p.6917-6925
• Main Authors: Nicoli, Francesca, Verschueren, Daniel, Klein, Misha, Dekker, Cees, Jonsson, Magnus P
• Format: Article
• Language: English
• Subjects: Applied sciences; Biomolecules; Biosensing Techniques - methods; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Deoxyribonucleic acid; DNA - analysis; DNA - chemistry; DNA - ultrastructure; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Exact sciences and technology; General equipment and techniques; Gold - chemistry; Gold - radiation effects; Heating; Instruments, apparatus, components and techniques common to several branches of physics and astronomy; Interrogation; Letter; Light; Low-dimensional structures (superlattices, quantum well structures, multilayers): structure, and nonelectronic properties; Metal Nanoparticles - chemistry; Metal Nanoparticles - radiation effects; Metal Nanoparticles - ultrastructure; Molecular electronics, nanoelectronics; Motion; Nanopores - ultrastructure; Nanostructure; Physics; Plasmonics; Porosity; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Sensors (chemical, optical, electrical, movement, gas, etc.); remote sensing; Surface and interface electron states; Surface Plasmon Resonance - methods; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Thermophoresis
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/nl503034j

Nanopores enable label-free detection and analysis of single biomolecules. Here, we investigate DNA translocations through a novel type of plasmonic nanopore based on a gold bowtie nanoantenna with a solid-state nanopore at the plasmonic hot spot. Plasmonic excitation of the nanopore is found to influence both the sensor signal (nanopore ionic conductance blockade during DNA translocation) and the process that captures DNA into the nanopore, without affecting the duration time of the translocations. Most striking is a strong plasmon-induced enhancement of the rate of DNA translocation events in lithium chloride (LiCl, already 10-fold enhancement at a few mW of laser power). This provides a means to utilize the excellent spatiotemporal resolution of DNA interrogations with nanopores in LiCl buffers, which is known to suffer from low event rates. We propose a mechanism based on plasmon-induced local heating and thermophoresis as explanation of our observations.