Plasmonic
biosensors enable development of new easy-to-use health tests
Aalto University
Researchers at Aalto
University, Finland, have developed a biosensor that enables creating a range
of new easy-to-use health tests similar to home pregnancy tests. The plasmonic biosensor can detect diseased exosomes even by the naked eye. Exosomes, important indicators of health conditions, are cell-derived vesicles that are present in blood and urine.
A rapid analysis by
biosensors helps recognize inflammatory bowel diseases, cancer and other
diseases rapidly and start relevant treatments in time. In addition to using
discovery in biomedicine, industry may use advanced applications in energy.
Researchers created a
new biosensor by depositing 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 used for making objects invisible in scientific tests. They efficiently reflect and absorb light. Plasmonic materials are based on the effective polarizabilities of metallic nanostructures.
Plasmonic materials have been used for making objects invisible in scientific tests. They efficiently reflect and absorb light. Plasmonic materials are based on the effective 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," says Professor Mady Elbahri from Aalto
University.
Plasmonic dipoles are
famous for their strong scattering and absorption. Dr. Shahin Homaeigohar and
Moheb Abdealziz from Aalto University explain that the research group has
succeeded in demonstrating the as-yet unknown 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," says Dr. Abdou Elsharawy from the University of Kiel.
The novel approach
enables a simple and cost-effective design of a perfect colored absorber and
creation of vivid interference plasmonic colors.
According to Elbahri,
there is no need to use of sophisticated fabrication and patterning methods. It
enables naked-eye environmental and bulk biodetection of samples with a very
minor change of molecular polarizability of even 0.001%.