New ability to characterize a single particle in a non-destructive manner

SERS Identification of Optically Trapped Molecule

The US Army has developed a new analytical method, based upon simultaneous exploitation of optical trapping and surface-enhanced Raman scattering (SERS) phenomena, sensitive enough to make positive identification of a suspected threat agent using only a single particle.

Apply for a License

Technology Description

The Technology:
The US Army Research Laboratory (ARL) is a nationally-recognized innovator of diagnostic biotechnologies and is currently focused on rapid characterization of potential biothreats.

The invented ARL system is comprised of a laser operating in the visible to near-infrared wavelength (approx. 650 to 1100 nanometers). The beam provides attractive and repulsive forces that can physically move and hold dielectric particles in a fashion akin to tweezers. This optical trap is proximal to a set up that enables analysis by SERS, where a generated surface-plasmon-resonance electric field yields a scattering spectrum unique to a subject particle.  The spectrum is background-corrected and then compared with published data via an automated chemometric system.

The ARL invention is practiced using commercial-off-the shelf components and supplies.  The system is non-invasive and non-destructive, does not suffer interference from water and is insensitive to the excitation wavelength.  The patent includes a method of particle detection analysis and an approach for building a library of enhanced particle scattering spectra.

  • Unique capability to characterize single particles with averaged linear dimension between 0.10 and 50 microns
  • Reduces analysis time to minutes, instead of hours or days needed with traditional methods
  • Commercial-off-the-shelf components apability to analyze single, dielectric particles with averaged linear dimension between 0.10 and 50 microns
  • Broad applicability to military, medical, food preparation, homeland security, law enforcement

The Opportunity:

  • Issued US Patent 7,515,269 available for license
  • TRL 5 – Fully-developed detection system, with data available
  • Potential for collaboration with US Army scientists and laboratory

Supplemental Technical Information:

For more information, contact:
Brian Metzger, PhD (406) 994-7782,

Licensing Instructions:

In order to apply for license to federally owned technologies, regulations require that specific information be provided regarding your company and plans for commercialization. This information will be incorporated in a license agreement which will be provided for your review prior to signature. All provided information will be considered proprietary and held confidential.

Apply for a License