An Ultrasensitive DNA Sensor for Hg²⁺ Assay Based on Electrodeposited Au/Carbon Nanofibers‐chitosan and Reduced Graphene Oxide

Abstract

An ultrasensitive electrochemical DNA sensor was designed for Hg2+ assay using cooperative signal amplification effect of electrodeposited Au/carbon nanofibers‐chitosan (DpAu/CNFs‐CS) and reduced graphene oxide (RGO). CNFs‐CS was prepared to modify gold electrode (AuE). Then, Au was electrodeposited on CNFs‐CS/AuE to form DpAu/CNFs‐CS/AuE for the first signal amplification. With TH as signal probe and ssDNA as recognition component, RGO/ssDNA and RGO/TH interaction were used for the second signal amplification. The prepared sensor had wider linear range of 0.0001–460 nM and lower detection limit of 5.7×10−5 nM, high selectivity, and performed well in Hg2+ assay of tap water.

A sensitive DNA biosensor based on the distance dependent quenching of Silica@Ru(bpy)32+‐chitosan‐GO electrochemiluminescence by Ferrocene@Gold nanoparticles

“…CS contains a plenty of hydrophilic amino groups and hydroxyl groups in its molecular structure, which can be used to modify the properties of other materials [27,28]. In this work, GO and CS were introduced into SiO 2 @Ru to enhance the affinity and electronic conductivity of nanocomposite, and to improve the ECL response characteristics of SiO 2 @Ru nanoparticles.…”