Imperial News

Enhanced Raman Spectroscopy Using Metallic Nanopores: Dr Joshua Edel, Imperial C

by Sima Fulford

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

 
Nanoletters

Michael P. Cecchini †, Aeneas Wiener ‡, Vladimir A. Turek †, Hyangh Chon §, Sangyeop Lee §, Aleksandar P. Ivanov †, David W. McComb , Jaebum Choo §, Tim Albrecht †, Stefan A. Maier ‡, and Joshua B. Edel *†

† Department of Chemistry, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom

‡ Department of Physics, Imperial College London, South Kensington Campus, London, SW7 2AZ, United Kingdom

§ Department of Bionano Engineering, Hanyang University, Ansan 426-791, South Korea

Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210, United States

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 solid-state 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 SERRS to provide rich vibrational information on the analyte, improving on current nanopore-based electrical and optical detection techniques. We show that the full vibrational spectrum of the analyte can be detected with ultrahigh spectral sensitivity and a rapid temporal resolution of 880 μs.
 

Keywords:

Raman spectroscopy; surface-enhanced Raman spectroscopy; nanoparticles; nanopore; plasmonics; nanoplasmonics; metallic nanopore; optical sensor; single molecule sensors