Extraordinary sensitivity enhancement by metasurfaces in terahertz detection of antibiotics.
We have detected trace amounts of molecules of antibiotics (kanamycin sulfate) dispersed on metasurfaces with terahertz (THz) spectroscopy. Utilizing the extraordinary optical transmission resonance of an array of square-shaped slits on a silicon substrate at ~0.3 THz, we were able to monitor varying concentrations of kanamycin sulfate as low as ~100 picogram/L. In contrast, the lowest detectable concentration of kanamycin sulfate on silicon without any metallic structure was ~1 gram/L. This dramatic ~10(10) times enhancement of sensitivity is due to the near-field enhancement of THz electric fields by the metamaterial structure. This result thus demonstrates the power and usefulness of metamaterial-assisted THz spectroscopy in trace molecular detection for biological and chemical sensing as well as for food product quality and safety inspection and control.
College of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P. R. China.
Lijuan
L
Xie
Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA.
Weilu
W
Gao
Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA.
Jie
J
Shu
College of Biosystems Engineering and Food Science, Zhejiang University, 866 Yuhangtang Road, Hangzhou 310058, P. R. China.
Yibin
Y
Ying
1] Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005, USA [2] Department of Physics and Astronomy, Rice University, Houston, TX 77005, USA [3] Department of Materials Science and NanoEngineering, Rice University, Houston, TX 77005, USA.
Junichiro
J
Kono
D000900:Anti-Bacterial Agents / Q000032:analysis*; D007612:Kanamycin / Q000032:analysis; D013499:Surface Properties; D055068:Terahertz Spectroscopy
D000900:Anti-Bacterial Agents; D007612:Kanamycin