Self‐Assembled Mercapto‐Compound‐Gold‐Nanoparticle‐Modified Carbon Paste Electrode for Potentiometric Determination of Cadmium(II)

Abstract

A new modified carbon paste electrode (CPE) based on a recently synthesized ligand [2-mercapto-5-(3-nitrophenyl)-1,3,4-thiadiazole] (MNT), self-assembled to gold nanoparticles (GNP) as suitable carrier for Cd(II) ion with potentiometric method are described. The proposed electrode exhibits a Nernstian slope of 29.4 AE 1.0 mV per decade for Cd(II) ion over a wide concentration range from 3.1 Â 10 À8 to 3.1 Â 10 À4 mol L À1 . The detection limit of electrode was 2.0 Â 10 À8 mol L À1 of cadmium ion. The potentiometric responses of electrode based on MNT is independent of the pH of test solution in the pH range 2.0 -4.0. It has quick response with response time of about 6 s. The proposed electrode show fairly good selectivity over some alkali, alkaline earth, transition and heavy metal ions. Finally, the proposed electrode was successfully employed to detect Cd(II) ion in hair and water samples.

Comparative studies of mercapto thiadiazoles self-assembled on gold nanoparticle as ionophores for Cu(II) carbon paste sensors

“…GNPs are commonly used for fabrication of modified carbon paste electrode in voltammetric and amperometric methods, but we applied GNP-carbon paste electrode for potentiometric method for the first time. In our previous work, we demonstrated that the carbon paste electrodes modified with sulfur-containing compounds self-assembled on gold nanoparticles constitute the excellent sensors for potentiometric determination of copper and cadmium cations [14,15].…”

Electrode Materials (Bulk Materials and Modification)

“…Gold nanoparticles in CPEs have been exploited for the detection of metal ions. 744,745 Other nanoparticles with electrocatalytic properties are metal oxides, some of them being used for environmental sensing (i.e., SiO 2 746 or ZrO 2 747) . Note that the particular case of nanosized materials will be treated in the next chapter.…”

Used gold nano-particles as an on/off switch for response of a potentiometric sensor to Al(III) or Cu(II) metal ions

“…GNPs are commonly used for fabrication of modified carbon paste electrode in voltammetric and amperometric methods, but we applied GNP-carbon paste electrode for potentiometric method. In our previous works, we demonstrated that the carbon paste electrodes modified with sulfur-containing compounds self-assembled on gold nano-particles constitute the excellent sensors for potentiometric determination of some metal cations [25][26][27]. The sol-gel route provides a useful method to prepare inorganic and organic-inorganic hybrid materials for use in chemical analysis.…”