Electrogeneration of Gold Nanoparticles on Porous-Carbon Paper-Based Electrodes and Application to Inorganic Arsenic Analysis in White Wines by Chronoamperometric Stripping

Abstract

This paper describes the development of simple, sustainable, and low-cost strategies for signal enhancement on paper-based carbon platforms through gold nanoparticles electrogenerated from small volumes of tetrachloroauric (III) acid solutions. Carbon ink is deposited on a hydrophilic working area of the paper delimited with hydrophobic wax. This maskless procedure is fast and cuts down ink waste. The connection of this working electrode to the potentiostat is ensured with the use of screen-printed electrodes (SPEs). Close contact of the whole area of both carbon electrodes improves the precision of the nanostructuration. Resulting gold-modified paper-based carbon working electrodes (AuNPs-PCWEs) were characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), scanning electron microscopy (SEM), and electron dispersion X-ray spectrometry (SEM/EDX). This methodology was applied for the first time to the inorganic arsenic determination in commercial white wines by chronoamperometric stripping of the electrodeposited As(0). In an optimized system, As(III) was reduced and deposited as As(0) on the nanostructured surface by applying a potential of -0.3 V during 180 s. Then, anodic stripping chronoamperometry was performed at +0.4 V. The analytical signal was the current recorded at 30 s. On the other hand, As(V) was chemically reduced to As(III) with 0.2 M KI, and total determination of arsenic could be carried out. As(V) was determined as the difference between total As and As(III). Then, this fast, simple and low-cost method can be employed for speciation purposes. Limits of detection for As(III) and total arsenic (in the presence of KI) are 2.2 μg L and 2.4 μg L, respectively, and indicate that this method is suitable for regulated quality control.

Disposable Sensors in Diagnostics, Food, and Environmental Monitoring

“…µPADs also cannot fully meet the needs of all disposable sensing applications, especially in terms of sensitivity . To improve their analytical performance, nanomaterials, including various nanoparticles or graphene nanomaterials, or biodegradable coatings (for example, using biopolymers such as chitosan) can be introduced to µPADs; however, this is a topic of on‐going research.…”

“…In contrast to traditional microbial culture methods performed in central laboratories, the approaches for detecting biological contaminants using disposable sensors are substantially faster, easy to use, and less expensive. Nonbiological contaminants, such as heavy metals and pesticides in food or drinking water, may not necessarily require antibodies or nucleic acids for detection and can be measured directly or enzymatically using disposable electrochemical transducers . Compared to laboratory‐based methods including liquid chromatography, they provide accurate enough results within minutes at a fraction of the cost.…”

“…For the fabrication of disposable electrochemical and colorimetric sensors for food analysis, cellulose and its derivatives, such as nitrocellulose, are among the materials most commonly used . Cellulose‐based materials have the obvious advantage that they can be ultralow cost, and various biomolecules can be immobilized or freeze‐dried on the hydrophilic surface without much effort.…”

In situ gold-nanoparticle electrogeneration on gold films deposited on paper for non-enzymatic electrochemical determination of glucose

“…The silver pseudo-reference and carbon counter electrodes of the SPCE card acted as external electrodes. In order to compare the electrochemical behavior of glucose using AuNPs paper-based carbon electrodes, drop-casted carbon electrodes were prepared as reported in a previous work [23].…”

Staple‐Based Paper Electrochemical Platform for Celiac Disease Diagnosis

“…In the design of a three‐electrode amperometric cell, electrodes have to be separated from each other. This could be made by: i) using multiple layers, ii) direct printing (e. g., pencil‐drawn, pen‐on‐paper, or laser scribing), iii) stencil‐ or screen‐printing electrodes, or iv) using external wire electrodes ,. Moreover, thin‐ or thick‐film working electrodes (WEs) do not require the use of stencils if reference and counter electrodes (RE, CE) are located on the opposite side of the film …”