Terahertz technology in diagnosis of glioma molecular markers

Abstract

Gliomas are invasive brain tumors with high rates of recurrence and mortality. It has been shown that specific markers for glioma's differential diagnostics are enantiomers of 2-hydroxyglutarate (L-2HG and D-2HG) in brain tissues and blood. These isomers have unique absorption peaks originating from vibrational and rotational transitions in their molecules. In particular, the peaks centered at 1.337 THz and 1.695 THz correspond to L-2HG and D-2HG isomers, respectively. The goal of this work is to develop highly efficient frequency-selective sensors for L-2HG and D-2HG isomers using the effect of nanoantenna-assisted plasmonic enhancement of THz absorption. Such an approach provides a noticeable increase in detection sensitivity versus direct non-resonant methods. In this paper, we present the numerical results of the design optimization for L-2HG and D-2HG sensors based on Si/SiO2-wafer-backed arrays of golden nanoantennas of linear geometry. The optimal structural parameters of the arrays found through integral averaging of the square of the surface electric field over an array unit cell are recommended for further nanolithographic fabrication of this kind of THz sensor.