Refining microbial potentiometric sensor performance with unique cathodic catalytic properties for targeted...

Area of Science:

• Environmental Science
• Electrochemistry
• Microbiology

Background:

• Traditional microbial electrochemical sensors are complex and face implementation challenges.
• Microbial potentiometric sensors (MPS) offer a simpler approach for environmental monitoring but have limitations.
• Existing MPS designs expose reference electrodes and lack microbial metabolism stimulation methods.

Purpose of the Study:

• To enhance microbial potentiometric sensor (MPS) performance through unique cathodic catalytic properties.
• To tailor biosensors for distinct environmental monitoring applications, including organic and toxic substance detection.
• To physically isolate sensing elements from the analyzed water sample.

Main Methods:

• Developed two types of MPS: one with and one without Platinum/Carbon (Pt/C) coating in the cathodic region.
• Physically isolated the anodic sensing region, cathodic region, and reference electrode from the water sample.
• Evaluated sensor performance based on response time, detection limits, reusability, and anode biofilm characteristics.

Main Results:

• The Pt/C-free sensor showed faster response (1 hour) and lower detection limits for BOD (1 mg L⁻¹) and acetic acid (1 mM).
• The Pt/C-coated sensor achieved a lower detection limit for formaldehyde (0.004%) in toxic substance monitoring.
• The Pt/C-free sensor demonstrated superior reusability, while the Pt/C-coated sensor exhibited increased anode biofilm thickness (Rhodococcus).

Conclusions:

• The study successfully developed enhanced microbial potentiometric sensors (MPS) with tailored cathodic catalytic properties.
• These improved biosensors offer customizable solutions for specific water quality monitoring scenarios.
• The developed sensors are simple, cost-effective, and show significant promise for practical environmental applications.