Pocketable Biosensor Based on Quartz-Crystal Microbalance and Its Application to DNA Detection

Area of Science:

• Analytical Chemistry
• Biosensor Technology
• Nanotechnology

Background:

• Quartz-Crystal Microbalance (QCM) is a sensitive mass-measurement technique.
• Existing highly sensitive QCM devices are typically large, benchtop instruments.
• There is a need for portable, field-deployable QCM biosensors.

Purpose of the Study:

• To fabricate a portable, battery-powered, IC card-sized QCM device.
• To demonstrate the device's capability as a label-free biosensor for DNA detection.
• To evaluate the sensitivity and specificity of the miniaturized QCM biosensor.

Main Methods:

• Miniaturization of QCM device by repurposing smartphone and wearable electronic components and batteries.
• Immobilization of receptors on the QCM sensor surface for molecular capture.
• DNA detection experiments using specific 10-mer DNA chains.

Main Results:

• Successfully fabricated a portable, IC card-sized QCM device.
• The device demonstrated high sensitivity in detecting specific 10-mer DNA chains.
• The QCM biosensor could discern single-base differences, comparable to benchtop devices.

Conclusions:

• The developed card-sized QCM device offers a portable and sensitive solution for biosensing.
• This miniaturized QCM technology is suitable for laboratory use and diverse field applications.
• The device advances the development of accessible, label-free biomolecular detection systems.