Polybrominated diphenyl ethers (PBDEs) are a common brominated flame retardant, which are commonly found in consumer products. Because they are not chemically bound to polymers, PBDEs are blended in during formation and have the ability to migrate from products into the environment. Studies suggest that PBDEs pose potential health risks such as hormone disruptors, adverse neurobehavioral toxins and reproductive or developmental effects. For this reason it is important to have the capability to sense the presence of PBDEs even in low concentrations.
Researchers at UC San Diego have Invented a highly sensitive nanostructured thin-film detector capable of identifying low concentrations (nano-molar) of Polybrominated diphenyl ethers (PBDEs) in aqueous solution. The invention utilizes a colloidal metasurface platform to carry out surface enhanced Raman spectroscopy in a small confined volume but over a large area. The metasurface is fabricated using an elastomer stamp that is coated with a monolayer of Ag nanocubes. This stamp can then be applied onto a gold or metallized surface containing the desired analyte to form a sandwich-type structure, encapsulating the analyte in the highly absorbing optical cavity of the metasurface. Following exposure of the sensor to a solution of interest, SERS measurements are taken using a 785 nm laser.
The following applications include:
The disclosed PDBE senor has the benefit of realizing orders of magnitude better signal-to-noise enhancements as compared to commercially available SERS based sensors. This improvement is due to the unique colloidal nanoparticles used in the fabrication process. The platform also provides a molecule-specific vibrational signature via the collection of Raman scattered photons.
A working prototype of the invention has been realized.
The invention is patent pending and available to license
PBDE, water quality, environmental sensing, nano-materials, Surface Enhanced Raman Spectroscopy