Flexible Polyester Screen‐printed Electrode Modified with Carbon Nanofibers for the Electrochemical Aptasensing of Cadmium (II)

Abstract

An aptasensor was prepared by immobilising a biotinylated aptamer selected for Cd(II) on an activated carbon nanofiber (CNF) and streptavidin modified a screen-printed electrode. The acid activated CNF was characterised by FTIR, CHNS elemental analysis and electron microscopy. Cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy (EIS) were used to characterise each step in the aptasensor preparation electrochemically. A detection limit of 0.11 ppb and a linear range of 2-100 ppb were obtained for Cd(II) with tolerance for other interfering species. The aptasensor was applied in real water samples and validated with ICPOES.

An Electrochemical Aptamer Biosensor for Bisphenol A on a Carbon Nanofibre‐silver Nanoparticle Immobilisation Platform

“…Of particular interest for this current work are carbon nanofibres (CNFs), which are one‐dimensional carbon‐materials with diameters around 50–100 nm and lengths around 0.5–100 μm, obtained using a simple electrospinning method. This synthesis method of CNFs provides advantages in terms of reproducibility, efficiency, high yield cost effectiveness [26, 27].…”

Water-Phase Exfoliated Biochar Nanofibers from Eucalyptus Scraps for Electrode Modification and Conductive Film Fabrication

“…According to the Randles–Sevcik theory for quasi-reversible systems, the electroactive surface area (ECSA) values were calculated for all sensors (equation reported in the Supporting Information), which were 9.3, 15.3, and 6.4 mm 2 for BH-SPE, BH-film, and bare-SPE, respectively. The ECSAs obtained with the BH-CNF-based sensors were comparable to other sensors modified with morphologically similar carbon nanomaterial, as electrospun-CNF (12 mm 2 ) and CNF (9.2 mm 2 ) were used to modify commercial screen-printed electrodes and flexible polyester SPE, respectively. As expected, the ECSA of the BH-film was slightly higher, since it is exclusively composed of BH-CNF.…”

Electrochemical Sensing Platform Based on Graphene Oxide‐chitosan for Simultaneous Determination of some Antihypertensive Drugs

“…Figure S3 illustrated the resulted CVs of 5 mM K3[Fe(CN) 6 ] 3−/4− containing 0.1 M KCl at the bare and modified electrodes at various scan rates ranging 10 to 400 mV.s −1 . For a reversible reaction, the Randles‐Sevcik equation has been reported as follows [29–31]: $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{\rm I}}_{{\rm p}{\rm C}{\rm \ }}={\rm \ }\left(2.69\times {10}^{5}\right){\rm \ }{{\rm n}}^{{3/2}}{\rm \ }{\rm A}{\rm \ }{{\rm D}}_{0}^{{1/2}}{{\rm \upsilon }}^{{1/2}}{{\rm C}}_{0}\hfill\cr}}$$$ …”

“…Figure S3 illustrated the resulted CVs of 5 mM K3[Fe-(CN) 6 ] 3À /4À containing 0.1 M KCl at the bare and modified electrodes at various scan rates ranging 10 to 400 mV.s À 1 . For a reversible reaction, the Randles-Sevcik equation has been reported as follows [29][30][31]:…”