Korean researchers have developed technology to detect Covid-19 variants using terahertz (THz) waves.
The Korea Institute of Science and Technology (KIST) said the doctors on Tuesday. Seo Mi-nah and Song Hyun-seok of the Sensor System Research Center used unlabeled THz metamaterials to quickly and accurately discriminate between variants of the Covid-19 virus.
THz metamaterials operate in THz electromagnetic waves. At a specific frequency, their transmission or reflectance is amplified.
The biomarker detection technology uses a highly sensitive, label-free THz metamaterial center that detects the protein unit, which plays a key role in viral penetration without changing the properties of the virus.
This technology can fill the gaps of conventional PCR tests and rapid antigen tests. Although PCR tests are very accurate, it takes more than four hours to get the result. Rapid antigen tests produce results in 20 minutes, but their accuracy is low.
The research team said THz electromagnetic waves have a very wide frequency band and can be used for spectroscopy, sensitive to the natural vibrations of biomolecules, to interpret unique information and differences in biological samples such as DNA and amino acids.
As the probability of THz interacting with biological samples is low and there is no technology to amplify the signals, it is difficult to directly detect samples in vivo.
The research team used metamaterials that amplify signals in a specific band of electromagnetic waves to overcome this shortcoming to develop a biomolecule diagnostic platform. This was to identify THz signals even in very small quantities.
After specifying amino acids with excellent absorption in the THz band, the research team created THz metamaterials to amplify the signal. Then, they scattered the samples on the surface of the metamaterials and analyzed the constant optical value of the samples to observe the THz signal change.
The results showed that the research team could infer sample characteristics and quantities, such as detection and charge quantity, polarity, and monomer hydrophobicity index, within minutes.
Also, they could identify virus variants with similar structures by detecting changes in amino acid units.
“It will become possible to use THz analysis to develop diagnostic technology to detect infectious disease and trace virus variants,” Dr Seo said.
The study, titled “Detection and discrimination of SARS-CoV-2 spike protein-derived peptides using THz metamaterials,” was published in Biosensors and Bioelectronics.