Exosomes are vesicles that are released by the body’s cells that end up in our blood, urine, and other bodily fluids. The importance and roles they play within our bodies still has to be elucidated, but there’s already a lot of signs that exosomes are biomarkers of disease and indicators of various cellular processes. Studying exosomes has been difficult because these particles are very rare and spotting them among a myriad of other things within bodily fluids is harder than finding a needle in a haystack.
Researchers at Aalto University in Finland have now developed a plasmonic sensor that allows for detection of exosomes with the naked eye! Plasmonic materials have very intense and unusual light absorption and reflection properties and the researchers were able to utilize these to spot refractive index changes between healthy and diseased exosomes.
Some details from the study abstract in journal Advanced Materials:
Plasmonic dipoles are famous for their strong absorptivity rather than their reflectivity. Here, the as-yet unknown specular reflection and the Brewster effect of ultrafine plasmonic dipoles, metaparticles, are introduced and exploited as the basis of new design rules for advanced applications. A configuration of “Plasmonic metaparticles on a blackbody” is demonstrated and utilized for the design of a tailored perfect-colored absorber and for visual detection of environmental dielectrics that is not readily done by extinction plasmonics. Moreover, the Plasmonic Brewster Wavelength (PBW) effect is introduced as a new platform for the naked-eye and bulk biodetection of analytes. The technique operates based on slight changes of molecular polarizability which is not detectable via conventional plasmon resonance techniques.
Study in journal Advanced Materials: Plasmonic Metaparticles on a Blackbody Create Vivid Reflective Colors for Naked-Eye Environmental and Clinical Biodetection…
Flashback: Acoustofluidics Pulls Exosomes from Whole Blood…
Via: Aalto University…
