Rapid Ultrasensitive Single Particle Surface-Enhanced Raman Spectroscopy Using Metallic Nanopores

Abstract

Nanopore sensors embedded within thin dielectric membranes have been gaining significant interest due to their single molecule sensitivity and compatibility of detecting a large range of analytes, from DNA and proteins, to small molecules and particles. Building on this concept we utilize a metallic Au solidstate membrane to translocate and rapidly detect single Au nanoparticles (NPs) functionalized with 589 dye molecules using surface enhanced resonance Raman Spectroscopy (SERRS). We show that due to the plasmonic coupling between the Au metallic nanopore surface and the NP, signal intensities are enhanced when probing analyte molecules bound to the NP surface. Although not single molecule, this nanopore sensing scheme benefits from the ability of SERS to provide rich vibrational information on the analyte, improving on current nanopore-based electrical and optical detection techniques. We show that the full vibrational band of the analyte can be detected with ultra-high spectral sensitivity, and rapid temporal resolution of 880 µs.

Precise Attoliter Temperature Control of Nanopore Sensors Using a Nanoplasmonic Bullseye

“…The bullseye structure was then milled into the gold side of the membrane using a focused ion beam (FIB, Ga + ) (see Figure 1A). 10 Figure 1B shows the cross section of our nanopore. As can be seen, only the center pore cuts through the entire membrane, the rings of the bullseye structure exist only in the gold film.…”

Through a Window, Brightly: A Review of Selected Nanofabricated Thin-Film Platforms for Spectroscopy, Imaging, and Detection

“…Fluorescence is the most likely optical technique to be used in conjunction with a nanopore, but one could imagine that a suitably structured gold film, separated by a well-defined nanopore gap containing an analyte, might also be used for surface-enhanced Raman spectroscopy. 20,27,46,61,90,[267][268][269][305][306][307][308][309][310][311][312][313][314][315] Extensions to Nanopore Arrays. We conclude our discussion of the merging of physical-and optical-based nanopore sensing and manipulation approaches, with the consideration of nanopore arrays.…”

Mechanical Properties of Nanoporous Au: From Empirical Evidence to Phenomenological Modeling

“…For this reason, NP Au also represents a candidate material for tunable surface-enhanced Raman spectroscopy [87,88]. Moreover, the residual Ag content affects and tunes the functionality of NP Au substrates in surface-enhanced Raman scattering [89].…”