A biosensor created at Aalto University enables developing a variety of new health tests quite like home pregnancy tests.
Visualizing the specular reflection color by a blackbody substrate. The carriers containing Ag nanoparticles are covered with various dielectrics of AlN, SiO2 and the composites thereof that are placed on a black background to enhance the reflectivity contrast of various colors at a normal angle of incidence. (Photo: Aalto University)
The plasmonic biosensor can detect diseased exosomes even by the naked eye. Exosomes, vital indicators of health conditions, are cell-derived vesicles that exist in urine and blood.
A quick analysis by biosensors helps identify cancer, inflammatory bowel diseases, and other diseases speedily and start applicable treatments in time. On top of using discovery in biomedicine, industry may use modern applications in energy.
Researchers developed a new biosensor by placing plasmonic metaparticles on a black, physical body that absorbs all incident electromagnetic radiation. A plasmon is a quantum of plasma oscillation. Plasmonic materials have been employed for creating objects invisible in scientific tests. They capably reflect and absorb light. Plasmonic materials are based on the operational polarizabilities of metallic nanostructures.
It is extraordinary that we can detect diseased exosomes by the naked eye. The conventional plasmonic biosensors are able to detect analytes solely at a molecular level. So far, the naked-eye detection of biosamples has been either rarely considered or unsuccessful.
Professor Mady Elbahri, Aalto University.
Plasmonic dipoles are well-known for their robust scattering and absorption. Dr. Shahin Homaeigohar and Moheb Abdealziz from Aalto University explain that the research team has been successful in showing the as-yet unidentified specular reflection and the Brewster effect of ultrafine plasmonic dipoles on a black body host.
We exploited it as the basis of new design rules to differentiate diseased human serum exosomes from healthy ones in a simple manner with no need to any specialized equipment.
Dr. Abdou Elsharawy, the University of Kiel.
The novel method enables a simple and economic design of an ideal colored absorber and formation of bright interference plasmonic colors.
According to Elbahri, there is no need for the use of advanced fabrication and patterning techniques. It enables naked-eye environmental and bulk biodetection of samples with a very negligible change of molecular polarizability of just 0.001%.
The research was published recently in Advanced Materials.