A Reconfigurable, Pulse-shaping Potentiometric Readout System for Bio-Sensing Transistors

Area of Science:

• Electrochemistry
• Biosensor Technology
• Integrated Circuit Design

Background:

• Potentiometric electrochemical sensors are crucial for detecting analytes but can suffer from charge accumulation.
• Existing readout systems may lack flexibility and high resolution for diverse biosensing applications.

Purpose of the Study:

• To develop a multi-modality readout system for potentiometric electrochemical sensors.
• To enhance sensor performance by reducing charge accumulation and improving signal digitization.
• To enable flexible and real-time monitoring for potential handheld medical devices.

Main Methods:

• Employing pulse modulation at the gate and drain of Bio-FET sensors to mitigate charge accumulation.
• Utilizing an oscillator-based architecture for signal digitization and integration.
• Adjusting stimulus signal parameters (duration, amplitude) and counting time for enhanced resolution.

Main Results:

• Demonstrated successful testing with Potassium Ferricyanide (K3[Fe(CN)6]) over a concentration range of 0.1-10 mM.
• Achieved real-time interpretation of results on an integrated micro-LCD.
• The system showed flexibility for various biosensing applications and concentrations.

Conclusions:

• The developed multi-modality readout system effectively addresses charge accumulation issues in potentiometric sensors.
• The oscillator-based architecture provides adjustable resolution for improved sensing capabilities.
• This technology holds promise for developing advanced, portable medical devices for rapid biomarker and ion analysis.