A Combined Raman/Single-Molecule Junction System For Chemical/Biological Analysis

Abstract

Researchers at the University of California, Davis have developed a device for multi-dimensional data extraction at the molecular level to allow one to simultaneously detect the presence of a single-molecule electrically, and to extract a chemical fingerprint to identify that molecule optically.

Full Description

Recent technological advancements in nanoscience have allowed for the study/manipulation of materials at the molecular and atomic levels yielding a better understanding of how molecular structure influences various chemical reactions, surface interactions, and charge transport dynamics. Instrumentation, including field-enhanced Raman spectroscopy and single-molecule characterization used for nanoscale characterization purposes have resulted in the development of novel techniques in genome sequencing. These techniques can be used to evaluate the vibrational and electronic structure of individual molecules; however, they have proved to be less effective than required for simultaneously extracting multi-dimensional data depicting the optical, electrical, and mechanical properties of individual molecules, in situ due to the complexity in performing these measurements. As a result of these limitations, improvements in single-molecule characterization techniques are required.

Researchers at UC Davis have developed a multidimensional tool capable of simultaneously characterizing both the structural and transport properties of individual molecules through the acquisition of tunneling currents and Raman spectra in a single device. Raman enhancement between two nano-electrodes, combined with direct charge transport measurements, allows for concurrently acquiring electrical, optical, and mechanical information about a single molecule. The correlation of electron transport measurements with enhanced Raman scattering of an individual molecule bound between two nanostructured electrodes results in evidence of single-molecule Raman scattering with millisecond temporal resolution. Such simultaneous data extraction provides information about the chemical fingerprint of a molecule, along with data on its configuration, information concerning the strain applied on individual chemical bonds, and how this relates to charge transport properties within the molecular junction.

Applications

• Molecular electronics 
• Chemical sensing, analysis 
• Spectroscopy, molecular identification

Features/Benefits

• Fast, millisecond temporal resolution using a simple device 
• Single molecule data acquisition; electrical, optical, mechanical, transport data

Patent Status

Additional Patent Pending