Platform

The Goal: Optimize Sensitivity, Work Toward Same-Shift Testing

From the optical biosensor system to sliica-fused capillaries, each component of CapWave's Searchlight^TM technology is designed to optimize sensitivity for food safety testing.  The sensitivity at 0.1 pg/mL enables a new level of performance.  Sample prep times at 8-12 hours.  Results in 22 minutes or less.   All contributing to the goal of on-site, same-shift testing.

The Concept

The science behind CapWave’s biosensor immunoassay technology draws from many disciplines: chemistry, immunology, chemical processing automation, microfluidics, wavelength optics and the development of advanced biosensors.

Capillaries

• Microfluidic capillary tubes hold the sample and also serve as an optical waveguide.
• The small capillary size increases the kinetics among the capture antibodies, the antigen and the detection antibodies.
• Fused silica tubes increase sensitivity as fluorescence detects the level of CFUs in the capillary.

Immunoassay

• Assay time is about 20 minutes, once the sample has been prepared and placed in the cartridge.  The assay has the ability to test multiple samples simultaneously.

Biosensor

• Pioneering advances in wave optics, evanescent wave theory and fluorescent immunochemistry lead to a high level of sensitivity for the device.
• The range of detection is a few bacterium in one milliliter of water.

Washing and Incubation

• High sensitivity allows the sample volume to be small, which also reduces the amount of reagent needed for washing.
• Incubation is executed by innovative thermal control units that do not require any moving parts.

Testing

Two assays for E. coli 0157:H7 and anthrax have been tested at the USDA Laboratory in Maryland and the Naval Research Laboratory (NRL) in Washington, D.C respectively. The CapWave system detected as few as 133 E. coli in 1 mL. That translates into as few as four bacterium detected in a 38 millimeter capillary.