Lead ion-selective electrodes based on polyphenylenediamine as unique solid ionophores.

Area of Science:

• Electrochemistry
• Materials Science
• Analytical Chemistry

Background:

• Lead(II) ion detection is crucial for environmental and health monitoring.
• Development of selective and sensitive ion-selective electrodes (ISEs) remains a key challenge.
• Polymeric materials offer tunable properties for novel sensor applications.

Purpose of the Study:

• To fabricate and characterize a novel membrane electrode for lead(II) ion detection.
• To evaluate the electrode's performance, including sensitivity, selectivity, and response time.
• To assess the electrode's applicability in real-world sample analysis.

Main Methods:

• Fabrication of a membrane electrode using semi-conducting poly(m-phenylenediamine) microparticles as a solid ionophore.
• Potentiometric measurements to determine the electrode's response characteristics (detection limit, slope, selectivity).
• Analysis of real-world samples (urine, tap water, river water) using the developed electrode.

Main Results:

• The electrode exhibited a low detection limit (6.31×10(-7) M) and a near-Nernstian slope (29.8 mV decade(-1)) for Pb(II).
• High selectivity was observed, with minimal interference from common metal ions, except at high Hg(II) concentrations.
• The electrode demonstrated a long lifetime (5 months), fast response time (14s), and successful application in real-world sample analysis with good recovery and repeatability.

Conclusions:

• The developed poly(m-phenylenediamine) based membrane electrode is a promising tool for sensitive and selective lead(II) ion detection.
• Its robust performance and applicability in complex matrices highlight its potential for environmental and clinical monitoring.
• This work contributes to the advancement of ion-selective electrode technology using novel polymeric materials.