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Dynamic Multiparameter Platelet Function Assessment Using a Capacitive Biosensor
Published on: May 2, 2025
Development and application of a real-time capacitive sensor
Booncharoen Wongkittisuksa1, Chusak Limsakul, Proespichaya Kanatharana
1Trace Analysis and Biosensor Research Center, Prince of Songkla University, Hat Yai, Songkhla 90112, Thailand.
Biosensors & Bioelectronics
|November 20, 2010
Summary
A novel capacitive sensor detects human serum albumin (HSA) in real-time using affinity binding. This biosensor offers a flexible and sensitive method for analyzing biological samples and modified electrode surfaces.
Area of Science:
- Biosensor technology
- Electrochemical sensing
- Surface science
Background:
- Real-time monitoring of molecular interactions is crucial for diagnostics.
- Capacitive sensing offers label-free detection capabilities.
- Evaluating electrode insulation properties is important for sensor stability.
Purpose of the Study:
- To develop a real-time capacitive sensor using a potentiostatic step method.
- To enable simultaneous measurement of current, capacitance, and resistance.
- To demonstrate the sensor's utility in detecting human serum albumin (HSA) and analyzing urine samples.
Main Methods:
- Development of a potentiostatic step-based capacitive sensor.
- Real-time data acquisition of current waveform, capacitance, and resistance.
- Utilizing human serum albumin (HSA) and anti-HSA affinity binding pairs for detection.
- Validation using equivalent circuits and comparison with a commercial potentiostat.
Main Results:
- The developed sensor accurately measured capacitance and resistance.
- Demonstrated real-time observation of affinity binding association and dissociation.
- Achieved comparable sensitivity to commercial potentiostats for HSA detection (P>0.05).
- Showed excellent agreement with immunoturbidimetric assays for HSA in urine samples (P>0.05).
Conclusions:
- The developed real-time capacitive sensor is effective for direct analyte detection.
- The system provides valuable insights into binding kinetics and electrode insulation.
- Potential applications include detecting other analytes, kinetic analysis, and thickness measurements.
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