A Microstrip Transmission Line Biosensor to Measure the Interaction between Microliter Aqueous Solutions and 1.0-17.0...

Area of Science:

• Biotechnology
• Electrical Engineering
• Materials Science

Background:

• Radio frequency (RF) biosensors offer noninvasive, label-free, and low-cost sensing.
• Existing devices require smaller volumes and enhanced measurement repeatability and sensitivity.

Purpose of the Study:

• To verify a millimeter-sized microstrip transmission line biosensor.
• To assess performance with microliter sample volumes across a 1.0-17.0 GHz frequency range.

Main Methods:

• Designed and tested a millimeter-sized biosensor with a microliter well.
• Conducted experiments to evaluate measurement repeatability, sensitivity, and methodology.
• Measured S-parameters of deionized water, Tris-EDTA buffer, and lambda DNA.

Main Results:

• Demonstrated high repeatability and sensitivity in detecting increasing concentrations of materials under test (MUTs), with a maximum error of 0.36%.
• Confirmed that lambda DNA in Tris-EDTA buffer repeatably alters S-parameters compared to buffer alone.
• Verified the biosensor's capability to measure electromagnetic energy interactions with MUTs in microliter quantities.

Conclusions:

• The developed RF biosensor achieves high repeatability and sensitivity for microliter sample volumes.
• This innovative design advances noninvasive, label-free biosensing capabilities.
• The biosensor shows promise for various applications requiring precise detection of biological and chemical substances.