Related Experiment Video
Updated: Mar 6, 2026
Use of Label-free Optical Biosensors to Detect Modulation of Potassium Channels by G-protein Coupled Receptors
Published on: February 10, 2014
Optical Ion Sensing Platform Based on Potential-Modulated Release of Enzyme
Jiawang Ding1, Enguang Lv1, Liyan Zhu1
1Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS); Shandong Provincial Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, P. R. China.
This study introduces a novel optical ion sensing platform using an ion-selective electrode (ISE) to trigger enzyme release for visual color changes. This versatile method enables sensitive ion detection in challenging solutions.
Area of Science:
- Electrochemistry
- Analytical Chemistry
- Materials Science
Background:
- Ion-selective electrodes (ISEs) are crucial for potentiometric ion activity measurements.
- Developing versatile optical sensing platforms for diverse ions remains a challenge.
- Enzyme-based colorimetric detection offers visual readout capabilities.
Purpose of the Study:
- To develop a general and versatile optical ion sensing platform.
- To integrate potentiometric ion sensing with enzyme-mediated colorimetric detection.
- To enable visual ion detection in complex sample matrices.
Main Methods:
- Utilizing a polymeric membrane ion-selective electrode (ISE) as a potentiometric transducer and reference electrode.
- Employing a working electrode with an iron-alginate-horseradish peroxidase (HRP) thin film for potential-modulated enzyme release.
- Triggering enzyme release via Fe3+ reduction modulated by the ISE potential.
- Detecting released enzyme activity through substrate oxidation and visual color change.
Main Results:
- Demonstrated successful optical ion sensing for both cations (e.g., NH4+) and anions (e.g., Cl-).
- Achieved visual color change indicating ion presence and activity.
- Validated the platform's functionality in colored and turbid solutions.
Conclusions:
- The proposed platform offers a general and versatile visual-sensing strategy for ions.
- This approach enables optical ion sensing in challenging sample conditions where traditional methods fail.
- The integration of ISEs with enzyme-based colorimetry provides a sensitive and accessible detection method.
