Gold-on-glass microwave split-ring resonators with PDMS microchannels for differential measurement in microfluidic...

Area of Science:

• Microwave Engineering
• Microfluidics
• Sensor Technology

Background:

• Lab-on-chip devices offer miniaturized solutions for sample analysis.
• Differential measurement techniques can improve sensor accuracy and reduce noise.
• Split-ring resonators are suitable for microwave sensing applications.

Purpose of the Study:

• To develop a microwave resonator sensor system for simultaneous differential measurement of liquid samples.
• To enhance sensing linearity and reduce noise through differential measurements.
• To demonstrate the system's compatibility with cost-effective and user-friendly applications.

Main Methods:

• Fabrication of gold split-ring resonators on glass substrates.
• Integration of polydimethylsiloxane microchannels for liquid handling.
• Implementation of a dual-resonator system for simultaneous reference and sample measurements.
• Utilizing differential signal processing to analyze sensor responses.

Main Results:

• Achieved reliable differential measurements with a sensor pair response error as low as 0.1%.
• Demonstrated improved sensing linearity using the differential measurement capability.
• Quantified glucose solutions in the range of 3.2-16.1 mM with a sensitivity of 0.16 MHz/mM.
• Validated the effectiveness of the paired resonator design for noise reduction.

Conclusions:

• The developed microwave resonator lab-on-chip sensor enables accurate and linear differential measurements.
• The system is suitable for low-cost, simple, and easy-to-handle sensing applications.
• Differential measurement significantly enhances the performance of microfluidic sensors.