Sensing by wireless reading Ag/AgCl redox conversion on RFID tag: universal, battery-less biosensor design

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Chemistry

Background:

• Integrating biosensors into the Internet-of-Things (IoT) is crucial for advancing healthcare.
• A key challenge is the lack of battery-less biosensor designs, limiting widespread adoption.

Purpose of the Study:

• To develop a novel battery-less biosensor-RFID tag for wireless sensing of biological redox reactions.
• To demonstrate a generalizable method for converting existing redox reaction sensors into battery-less RFID tags.

Main Methods:

• Utilized silver nanoparticles (AgNPs) integrated into an RFID tag antenna.
• Employed gold nanoparticles (AuNPs) to facilitate electron transfer between enzymes and AgNPs.
• Demonstrated HRP-catalyzed conversion of AgNPs to AgCl upon reaction with hydrogen peroxide, altering tag impedance.

Main Results:

• Successfully created battery-less biosensor-RFID tags for detecting hydrogen peroxide and glucose.
• Showcased the critical role of AuNPs in enabling rapid electron transfer for efficient sensing.
• Observed significant impedance changes in the RFID tag due to AgNP conversion.

Conclusions:

• A fast and versatile route for creating battery-less sensor-RFID tags for redox reactions has been established.
• This technology has broad applicability for sensing various biological and non-biological catalysts.
• The developed system offers a promising solution for advancing wireless healthcare monitoring within IoT frameworks.