Application of terahertz technology for chiral molecular sensing

Chiral molecule sensing is vital across fields such as pharmaceuticals, agrochemicals, and biomedicine due to the distinct biological activities of enantiomers. Traditional chiral detection methods suffer from limitations including complex sample preparation, low sensitivity, and potentially damaging high-energy photons. Terahertz (THz) technology, operating in the 0.1–10 THz range, offers a promising alternative by probing low-frequency vibrational and rotational modes intrinsic to chirality with non-destructive, low-energy photons. This review presents recent advancements in THz-based chiral sensing, focusing on terahertz time-domain spectroscopy (THz-TDS), circularly polarized THz techniques, and metamaterial-enhanced THz sensors. We discuss the physical mechanisms underlying chiral responses in the THz band and evaluate technological innovations that enhance detection sensitivity and enantioselectivity. Challenges such as limited sensitivity, environmental interference, and device complexity are highlighted, alongside emerging solutions including chip-scale THz sources, and artificial intelligence-assisted data analysis.