Reusable terahertz metasurface microfluidic sensor with enhanced sensitivity for trace liquid analysis.

Area of Science:

• Terahertz (THz) sensing technology
• Metasurface sensor development
• Microfluidics for chemical analysis

Background:

• Conventional THz sensing platforms face challenges with low sensitivity and detecting trace amounts of analytes.
• Existing metasurface sensors require improvement for enhanced detection capabilities.

Purpose of the Study:

• To develop a reusable, high-sensitivity THz metasurface sensor integrated with an ultra-thin microfluidic channel.
• To overcome limitations in sensitivity and trace solution detection in current THz sensing platforms.

Main Methods:

• Comprehensive numerical simulations were conducted to design and optimize the sensor.
• Experimental validation was performed to confirm the sensor's performance.
• Integration of a 4.1 µm ultra-thin microfluidic channel with a THz metasurface.

Main Results:

• Achieved a sensitivity of 0.565 THz/RIU for minute analyte volumes (0.4 µL).
• Demonstrated a 2.58-to-5.64-fold enhancement in sensitivity compared to conventional THz metasurface structures.
• Measured significant resonance frequency shifts for various analytes including ethanol, methanol, glycerin, and water.

Conclusions:

• The developed THz metasurface sensor offers high sensitivity for detecting trace amounts of both polar and non-polar analytes.
• This advancement has significant implications for biochemical sensing and aqueous solution analysis.
• The sensor's reusability and enhanced sensitivity represent a major step forward in THz sensing technology.