Spontaneous Deposition of Prussian Blue on Multi-Walled Carbon Nanotubes and the Application in an Amperometric Biosensor

Abstract

A simple method has been developed for the spontaneous deposition of Prussian blue (PB) particles from a solution containing only ferricyanide ions onto conducting substrates such as indium tin oxide glass, glassy carbon disk and carbon nanotube (CNT) materials. Formation of PB deposits was confirmed by ultraviolet-visible absorption spectrometry and electrochemical techniques. The surface morphology of the PB particles deposited on the substrates was examined by atomic force microscopy and scanning electron microscopy. CNT/PB composite modified glassy carbon electrodes exhibited an electrocatalytic property for hydrogen peroxide reduction. These modified electrodes exhibited a high sensitivity for electrocatalytic reduction of hydrogen peroxide at −0.05 V (vs. Ag|AgCl), probably due to the synergistic effect of CNT with PB. Then, CNT/PB modified electrodes were further developed as amperometric glucose biosensors. These biosensors offered a linear response to glucose concentration from 0.1 to 0.9 mM with good selectivity, high sensitivity of 0.102 A M−1 cm−2 and short response time (within 2 s) at a negative operation potential of −0.05 V (vs. Ag|AgCl). The detection limit was estimated to be 0.01 mM at a signal-to-noise ratio of 3.

Detection of Hydroxyl Radicals Using Cerium Oxide/Graphene Oxide Composite on Prussian Blue

“…The increase of sensor conductivity is explained with an intrinsic characteristic of PB as an electrocatalyst. PB is well-known for its redox catalysis that increases a rate of electron transfer in a redox reaction between an electrode surface and electrolyte in a solution [ 52 , 53 ]. The addition of a PB layer on the electrode surface as an interlayer between the electrode and the CeNP/GO composite layer can facilitate the electron transfer resulting in an increase in the sensor conductivity [ 54 , 55 ].…”

Single-walled carbon nanotubes as a reducing agent for the synthesis of a Prussian blue-based composite: a quartz crystal microbalance study

“…28 The role of nanocarbons has also been hypothesized by some studies to go beyond that of the conductive particle carrier that optimizes the PB particle size and electrode surface area. The synthesis reaction of PB on nanocarbons has been proposed to proceed by the carbon materials itself 33,34 or the functional entities on its surface 35 acting as a reducing agent by providing the electrons needed for the reaction to proceed. This hypothesis is difficult to confirm when graphene or multiwalled carbon nanotubes (MWCNTs) are used 30,36,37 because the possibility and direction of electron transfer depend on the electronic structure of the material and the value of its Fermi level energy in relation to the redox potential of the synthesis reaction.…”

Electrochemical immunosensor for alpha‐fetoprotein based on prussian blue‐carbon nanotube@polydopamine

“…Recently, the electrochemical immunoassay has attracted tremendous attention owing to its high sensitivity, low cost, fast analysis and easy miniaturisation [8]. Prussian blue (PB), as a electron mediator, a typical hexacyanoferrate with a face‐centred cubic lattice structure, was used in electrochemical systems for the detection of biomolecules detection because of its high redox activity, excellent electrocatalytic properties, good electrochemical reversibility and high thermal stability [9, 10], However, the bottleneck of PB usage is easily leaking and destroyed, and lost activity in weak alkaline environment result the short lifetime of these PB‐based electrochemical sensors. To solve this problem, PB was load on the carbon nanotubes (CNTs) not only to increase stability of PB, but also to improve the electrical conductivity of nanocomposites, because CNTs has excellent physical and chemical properties, such as excellent electrical conductivity, high specific surface area and mechanical strength, and great chemical stability [11, 12].…”