Electroanalytical Studies on Cobalt(II) Ion‐Selective Sensor of Polymeric Membrane Electrode and Coated Graphite Electrode Based on N₂O₂ Salen Ligands

Abstract

Poly(vinyl chloride)-based membranes of salen ligands, 2-((E)-((1R,2S)-2-((E)-5-tert-butyl-2-hydroxybenzylideneamino)cyclohexylimino)methyl)-4-tert-butyl phenol (S 1 ) and 2-((E)-((1R,2S)-2-((E)-3,5-di-tert-butyl-2-hydroxybenzylideneamino)cyclohexylimino)methyl)-4,6-di-tert-butylphenol (S 2 ) were fabricated and explored as cobalt(II) selective electrodes. The performance of the polymeric membrane electrode (PME) and coated graphite electrode (CGE) were compared and it was observed that CGE showed a wide working concentration range of 1.1 10 À8 to 1.0 10 À1 mol L À1 with a limit of detection of 7.0 10 À9 mol L À1 exhibiting the Nernstian slope 29.6 mV/decade of activity in the pH range 3.0-9.0. It was used for the determination of cobalt(II) ions in water, soil, beer, pharmaceutical samples and medicinal plants and would be used as an indicator electrode in potentiometric titration with EDTA.

Electrochemical Selective Determination of Uranyl Ions Using PVC Membrane Sensor

“…The dynamic response time of the electrodes was evaluated by measuring the average time required to reach a potential within ±1 mV of the final equilibrium potential value after successive immersion of the electrode in a series of uranyl solutions each having a 10‐fold concentration difference and the results are given in Figure . It was found that the propsed sensor quickly reached its equilibrium potential values in the whole concentration (1.0×10 −7 −1.0×10 −1 mol L −1 ) within 20 s. The low response time is probably due to the fast exchange kinetics of the complexation‐decomplexation of UO 2 2+ with the ionophore at the solution‐membrane interface .…”

Current State of Sensors and Sensing Systems Utilized in Beer Analysis

“…The 2-Salen ligands were used as cobalt-selective electrodes, and polymeric membrane electrode (PME) and coated graphite electrode (CGE) were compared, and it was observed that the CGE showed a limit detection of 7 nM. It was used successfully for the detection of cobalt in soil, beer, and water [137]. A bridge-modified 4-tertbutylthiacalix arene was used as an electroactive material for the preparation of a cobalt-selective sensor.…”

A comparative study on fabrication of Mn2+ selective polymeric membrane electrode and coated graphite electrode

“…However such materials are not available in abundance, which has made the development of ISE a slightly difficult job. Nevertheless in recent years some new groups of compounds such as Schiff bases [27][28][29], porphyrins [30,31], calixaranes [32,33], macrocyclic compounds [34,35] and other group of compounds [36,37] have been developed which have a coordinating cavity and due to which they tend to show high affinity for some particular metals and poor for others. Among these groups, Schiff bases are the item of choice, because it is easy to form them with varying cavity size.…”