The Simultaneous Electrochemical Detection of Catechol and Hydroquinone with [Cu(Sal-β-Ala)(3,5-DMPz)2]/SWCNTs/GCE

Abstract

A glassy carbon electrode was modified with a copper(II) complex [Cu(Sal-β-Ala) (3,5-DMPz)2] (Sal = salicylaldehyde, β-Ala = β-alanine, 3,5-DMPz = 3,5-dimethylpyrazole) and single-walled carbon nanotubes (SWCNTs). The modified electrode was used to detect catechol (CT) and hydroquinone (HQ) and exhibited good electrocatalytic activities toward the oxidation of CT and HQ. The peak currents were linear with the CT and HQ concentrations over the range of 5–215 μmol·L−1 and 5–370 μmol·L−1 with corresponding detection limits of 3.5 μmol·L−1 and 1.46 μmol·L−1 (S/N = 3) respectively. Moreover, the modified electrode exhibited good sensitivity, stability and reproducibility for the determination of CT and HQ, indicating the promising applications of the modified electrode in real sample analysis.

The Cu-MOF-199/single-walled carbon nanotubes modified electrode for simultaneous determination of hydroquinone and catechol with extended linear ranges and lower detection limits

“…The major interferences in the simultaneous determination of HQ and CT (100 µmol·L −1 ) come from the coexisting substances, which may lead to an overlapping with the existing peaks [36]. …”

“…The SWCNTs suspension (0.1 mg·mL −1 ) was prepared as described previously [36]. First, SWCNTs were mixed with a mixture solution of the concentrated H 2 SO 4 /HNO 3 (V 98 H2SO4 :V 65 HNO3 =3:1) in a ice-water bath and then refluxed for 3 h at 80 in a water bath.…”

Amperometric Tyrosinase Biosensor Based on Carbon Black Paste Electrode for Sensitive Detection of Catechol in Environmental Samples

“…Catechol, also known as pyrocatechol or 1,2‐dihydroxybenzene, is an ortho‐isomer of benzenediols with molecular formula C 6 H 4 (OH) 2 . It has been widely used in a variety of applications including production of pesticides and flavouring agents and as precursor in the development of perfumes and pharmaceuticals [1]. Catechol is classified as an environmental pollutant due to the toxicity to humans (lethal in the range of 50–500 g kg −1 ), animals, plants and aquatic organisms.…”

A Nano-Sepiolite Clay Electrochemical Sensor for the Rapid Electro–Catalytic Detection of Hydroquinone in Cosmetic Products

“…Due to its high toxicity, several methods have been established for the determination, such as high performance liquid chromatography, 2 fluorescence, 3 chemiluminescence, 4 spectrophotometry, [5][6] gas chromatography-mass spectrometry, 7 capillary electro-chromatography, 8 and electrochemical methods. [9][10][11][12][13] Most of the methods, in particular chromatographic methods, are both time consuming and based on the use of organic liquids in excess volumes. Electrochemical techniques for hydroquinone assay are cost effective, fast and highly sensitive.…”