Cysteamine Capped Silver Nanoparticles and Single‐walled Carbon Nanotubes Composite Coated on Glassy Carbon Electrode for Simultaneous Analysis of Hydroquinone and Catechol

Abstract

A stable complex of silver nanoparticles (Ag NPs) capped by cysteamine (Cst) together with single‐walled carbon nanotube (CNTs) was used to modify a glassy carbon electrode (GCE) for simultaneous detection of hydroquinone (HQ) and catechol (CT). The resulting electrode (AgCst‐CNTs/GCE) showed excellent electrocatalysis and reversibility towards this electroactive pair. The peak separations of their oxidation‐reduction peaks decreased significantly, compared with those of the unmodified GCE. The signal responses of the AgCst‐CNTs/GCE were 5‐fold higher while its peak potential separation remained unchanged (ca. 130 mV), compared to the CNTs‐modified GCE. The oxidation peak currents obtained for HQ and CT exhibited linearly from submicromolar to hundred micromolar concentrations without any cross‐interference. The modified electrode possessed a very large active surface area with a detection limit (S/N=3) of 10 and 40 nM for HQ and CT, respectively. The sensor was demonstrated for the analysis of river water and topical cream as evinced by high accuracy and reproducibility.

Electrochemical sensors for the safety and quality control of cosmetics: An overview of achievements and challenges

“…[15] with permission from the Royal Society of Chemistry Nowadays, the effective simultaneous detection of phenolic compounds that have analogous chemical features is a subject of major study interest in the field of analytical chemistry [18]. Because of the similar electrochemical behaviour of HQ, RS, and CC, their redox peaks tend to overlap and cannot be effectively distinguished using conventional glassy carbon electrodes [19]. Therefore, to improve the detection sensitivity and selectivity of electrochemical sensors, it is necessary to search for new nanomaterials that are eco-friendly, economical, and show good catalytic performance.…”

“…The nanocomposite possesses adequate reproducibility, good stability and acceptable recoveries for wastewater and cosmetic samples analyses. Butwong et al [19] described a simple strategy for the fabrication of a new modified electrode exploiting the synergetic effect of CNTs and AgNPs capped by cysteamine (Cst) for simultaneous detection of HQ and CC [19]. Cysteamine stabilized AgNPs and binds strongly to CNTs to form a stable and sensing layer on a GCE surface.…”

Flexible Transparent Electrode Characteristics of Graphene Oxide/Cysteamine/AgNP/AgNW Structure

“…AgNW solution (DT-AgNW-N30-1EOH, ditto technology Co. Korea) of 1% by weight in ethanol was diluted to obtain the ratio of ethanol:AgNW = 9:1 wt.%. GCA was synthesized as follows [22]. First, AgNO 3 (0.0100 g, 6 × 10 −5 mol) was stirred in distilled water (5 mL) at room temperature for 5 min, followed by the addition of cysteamine dihydrochloride (0.0135 g in 2 mL of distilled water).…”

Use of an in silico knowledge discovery approach to determine mechanistic studies of silver nanoparticles-induced toxicity from in vitro to in vivo

“…PVP is a high-molecular-weight polymer; though also non-covalently conjugated to the silver surface, it introduces steric repulsion to ensure greater stability [ 8 ]. By contrast, amines (e.g., cysteamine) covalently stabilize AgNPs via formation of Ag-sulfur bonds [ 9 ]. Citrate-mediated stabilization renders negative charges to AgNPs surface, while cysteamine-stabilized AgNPs surface appears to be positively charged.…”