Copper(II)-selective membrane electrodes based on some recently synthesized mixed aza-thioether crowns containing a...

Area of Science:

• Analytical Chemistry
• Electrochemistry
• Materials Science

Background:

• Mixed aza-thioether crowns are novel ligands with potential applications in ion sensing.
• 1,10-phenanthroline derivatives offer unique coordination properties for metal ion complexation.
• PVC-membrane electrodes are widely used for potentiometric ion determination.

Purpose of the Study:

• To synthesize and characterize three novel mixed aza-thioether crown ligands.
• To investigate the efficacy of these ligands as ion carriers in copper(II)-selective PVC-membrane electrodes.
• To evaluate the performance of the developed electrodes for copper(II) ion detection and quantification.

Main Methods:

• Synthesis of three mixed aza-thioether crowns incorporating a 1,10-phenanthroline moiety.
• Fabrication of PVC-membrane electrodes using the synthesized ligands as ionophores.
• Potentiometric measurements to assess electrode response, selectivity, detection limit, and operational stability.
• Application of the electrodes for direct determination and potentiometric titration of copper(II) ions.

Main Results:

• The electrode based on ligand L1 demonstrated a Nernstian response for Cu(2+) over a broad concentration range (2x10(-1) to 1x10(-5) M).
• A low limit of detection (8.0x10(-6) M) and a fast response time (15 s) were achieved.
• The membrane exhibited excellent selectivity for Cu(2+) over various interfering ions and stability for over 3 months.
• The electrode performed effectively in the optimal pH range of 2.5-5.5.

Conclusions:

• The developed PVC-membrane electrode utilizing the L1 ligand shows high potential for sensitive and selective determination of copper(II) ions.
• The sensor's performance characteristics make it suitable for direct potentiometric analysis and titrations.
• Mixed aza-thioether crowns are promising ionophores for the development of advanced electrochemical sensors.