Double-layer membrane framework-based gold microelectrode for determination of natural labile copper in complex water...

Area of Science:

• Electrochemistry
• Environmental Science
• Materials Science

Background:

• Copper (Cu) is vital for plankton but toxic at high concentrations, posing ecological risks.
• Accurate determination of low-concentration labile copper (Cu_Labile) in complex waters is challenging.
• Electrode fouling by biological and particulate matter hinders environmental monitoring.

Purpose of the Study:

• To develop a sensitive and anti-fouling electrochemical sensor for Cu_Labile determination.
• To enhance the detection performance of gold microelectrodes in environmental water samples.
• To enable real-time, in situ monitoring of copper dynamics in aquatic ecosystems.

Main Methods:

• Fabrication of a gold microelectrode (μ-GE) functionalized with a double-layer membrane (agarose gel and Nafion).
• Electrochemical characterization and performance evaluation of the LGL/Nafion/μ-GE sensor.
• Application of the sensor for Cu_Labile determination in natural seawater and algae culture media.

Main Results:

• The LGL/Nafion/μ-GE demonstrated significantly enhanced voltammetric response and stability.
• Achieved a low detection limit of 0.043 nM for Cu²⁺ with two linear ranges (0.5–10 nM and 10–1000 nM).
• Successfully applied the sensor for in situ, real-time monitoring of Cu_Labile in Synechococcus sp. PCC 7002 culture.

Conclusions:

• The developed LGL/Nafion/μ-GE offers high sensitivity and excellent anti-biofouling properties.
• The sensor is effective for determining Cu_Labile in complex environmental water samples.
• Enables continuous, real-time monitoring of labile copper, advancing ecological and toxicological studies.