Copper(II) Ion‐Selective Electrodes Based on Dithiosalicylic and Thiosalicylic Acids

Abstract

Potentiometric carbon paste electrodes for copper(II) based on dithiosalicylic and thiosalicylic acids are described. The sensor based on dithiosalicylic acid (DTS) exhibits a linear response with a nearly Nernstian slope of 27.7 mV per decade, whereas the electrode based on thiosalicylic acid (TS) shows a super-Nernstian slope. The limits of detection for the DTS sensor and the TS sensor are 10 À 7.9 and 10 À 6.3 M for copper(II) activity, respectively. Selectivity coefficients are tabulated, and the influence of the pH on the response of these ISEs is studied. The DTS electrode is successfully used for potentiometric titration of humic acids with copper in order to get more information about complexing properties of these acids.

Potentiometrie Carbon Paste Sensors for Lead(II) Based on Dithiodibenzoic and Mercaptobenzoic Aeids

“…Besides, in previous studies with a similar nonNernstian behavior, this method was used and good results were obtained. 27,35 As can be seen in Table 3, the obtained data for MSM are similar to that obtained with MPM. It can be observed, that the sensor based on DTB acid exhibited better selectivity.…”

“…[26][27][28] Paraffin oil was added and mixed until a uniform paste was obtained. Then, the carbon paste was packed into the end of a polypropylene syringe (ca.…”

“…The same behavior has been observed in previous studies with other potentiometric sensors. 27,28,34 Therefore, the electrode surface must be renewed when the lead(II) ion concentration in the test solution is lower than 1 × 10 -5 M.…”

“…In our group, potentiometric CMCPEs based on ligands and on metal complexes have been developed. [26][27][28] In this paper, we report on the potentiometric response to lead ions of CMCPEs based on dithiodibenzoic (DTB) and mercaptobenzoic (MB) acids. These ligands were chosen as modifiers, because they present an appropriate structure to form metal complexes.…”

Synthesis and Characterization of Zinc(II)-Complexes with S-Alkyl Derivatives of Thiosalicylic Acid

“…Thiosalicylic acid and its derivatives are used in chemical analysis (8)(9)(10)(11), in dermatology (12,13), and in the treatment of various diseases (14,15).…”