Microdroplet-Mediated Enzyme Activity Enhancement for Potentiometric Sensing of Peroxidase in Soil

Yinhao Li ^1,2, Jiawang Ding ^1,2, Wei Qin ^1,3,4,2

⁰CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, People's Republic of China.

Analytical Chemistry +

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March 10, 2025

View abstract on PubMed

Summary

A novel potentiometric sensor enables rapid, on-site measurement of soil enzyme activity. This breakthrough allows for direct field analysis of soil health and environmental stress responses.

Area Of Science

Environmental Science
Analytical Chemistry
Biochemistry

Background

On-site enzyme activity measurements in soil are crucial for evaluating soil health and sustainable management.
Existing methods lack the capability for direct, in-field analysis of soil enzyme activity.
There is a significant need for advanced sensor technology to address this gap.

Purpose Of The Study

To develop a novel potentiometric sensor for rapid, direct, and in-field analysis of soil enzyme activity.
To enable simultaneous soil particle separation and enzyme extraction within a single device.
To enhance enzyme activity measurements through microdroplet mediation for improved potentiometric detection.

Main Methods

A potentiometric sensor was designed for in-field soil enzyme activity analysis.
The sensor integrates soil particle separation and enzyme extraction.
Peroxidase activity was measured using 3,3',5,5'-tetramethylbenzidine as a substrate, with microdroplet enhancement.

Main Results

The developed sensor achieved a low detection limit of 10<sup>-7</sup> U mL<sup>-1</sup> for peroxidase activity within 5 minutes.
The sensor demonstrated excellent sensitivity and anti-interference capabilities in field measurements.
Successful deployment was shown for analyzing peroxidase activity in *Suaeda salsa* rhizosphere soil under salinity stress.

Conclusions

The potentiometric sensor offers a viable solution for on-site soil enzyme activity monitoring.
This technology has significant potential for evaluating soil health and understanding plant responses to environmental stresses.
The sensor's design facilitates rapid, direct, and reliable field measurements.

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