Cost-Effective Electrochemical Sensor Based on Carbon Nanotube Modified-Pencil Electrode for the Simultaneous Determination of Hydroquinone and Catechol

Abstract

In this study, the cost of working electrode was reduced greatly by replacing glassy carbon electrode (GCE) with 2B pencil. The pencil lead was modified with carbon nanotubes (CNTs) for simultaneous and quantitative detection of hydroquinone (HQ) and catechol (CT). The surface morphology of CNT-modified pencil electrode (PE-CNT) was studied by scanning electron microscopy (SEM) whereas electron transfer properties were evaluated through electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). This electrode evinced an enhanced redox reversibility and superior electrocatalytic performance concerning HQ and CT. Consecutive concentration variation studies exhibited linearity in oxidation peak responses up to 300 μM for each of the analytes with a detection limit (S/N = 3) as low as 1.5 and 0.7 μM for HQ and CT, respectively. We proposed a possible mechanism for their sensitive detection. The developed sensor was successfully examined for real sample analysis with tap water and it exhibited a stable and reliable recovery data with high reproducibility. The cost of the 2B pencil is 1000 times lower than that of GCE. Thus, the 2B pencil can be a good alternative to GCE in electrochemical sensor fabrication due to its economic advantage.

Porous tal palm carbon nanosheets: preparation, characterization and application for the simultaneous determination of dopamine and uric acid

“…However, bare electrodes oen exhibit poor reproducibility, a surface fouling effect and may ultimately fail to separate individual identities during concurrent detection. 11 Various modiers, such as precious metal nanoparticle-modied carbon materials, 8 reduced graphene oxide, 10 graphene oxide, 11 conducting polymer, 12 carbon nanotube 13 and porous carbon materials, 14,15 have been reported for the modi-cation of conventional electrodes. Among all of the abovestated materials, porous carbon has been most widely utilized as an electrode modier.…”

Electrochemical Sensing Platforms of Dihydroxybenzene: Part 1 – Carbon Nanotubes, Graphene, and their Derivatives

“…In most electrochemical sensing devices, GCE is used as a substrate, which is costly. To reduce this cost, Ahammad and his group [144] prepared a CNT‐based electrochemical sensor using a pencil electrode to detect dihydroxybenzene, as shown in Figure 12. The sensor produced well‐defined oxidation peaks for HQ and CT at an optimum pH value of 7.0.…”

“… Preparation of PE and PE‐CNT for the simultaneous determination of HQ and CT. Reproduced with permission [144] . Copyright 2018, The Electrochemical Society.…”

Semi-circular sweep voltammetry. Bio-analytical applications

“…The cyclic voltammetric response of a 1:1 mixture of 0.5 mM hydroquinone (HQ) and catechol (CC) was first explored in pH 7.4 PBS buffer at an unmodified GC electrode, a carbonnanotube modified screen printed electrode (CNT-SPE) and a MWCNT modified GC (MWCNT/GC) electrode. In the light of recently-developed voltammetric sensors for the dihydroxybenzene isomers using carbon-nanotube modified carbon-based electrodes (Ahammad et al 2018;Hu et al 2012;Wang et al 2007;Yue et al 2013;Zhao et al 2009) MWCNTs/GCs were prepared using a simple dropcast method fully described in section S1.2…”