Disposable superoxide anion biosensor based on superoxide dismutase entrapped in silica sol–gel matrix at gold nanoparticles modified ITO electrode

Abstract

A novel disposable biosensor based on direct electron transfer of superoxide dismutase (SOD) was fabricated for the determination of superoxide anion. The biosensor was constructed by electrodeposition of gold nanoparticles (GNPs) on the indium tin oxide (ITO) electrode and then immobilization of SOD in silica sol-gel (SG) network in the presence of cysteine on GNPs/ITO modified electrode surface. The distribution of GNPs on ITO electrode surface was examined by scanning electron microscopy (SEM). The immobilized SOD exhibited high catalytical activity towards superoxide anion. Parameters affecting the performance of the biosensor were also investigated. A linear calibration curve was obtained over the range from 0.08 to 0.64 microM with a correlation coefficient of 0.9937. The resulted biosensors were demonstrated to possess striking analytical properties for superoxide anion determination, such as high sensitivity, good accuracy, and long-term stability. It provides a promising platform for the fabrication of disposable biosensors.

Carboxymethylcellulose–gelatin–superoxidase dismutase electrode for amperometric superoxide radical sensing

“…This enzyme concentration giving the highest response is lower than for the biosensors developed by Di The measurement solution should be operated at a constant and high stirring speed (1,000 rpm) to acquire reproducible results. A peak-like response was observed, which is in agreement with a report by other worker [28,33,[36][37][38]. If only a certain amount is added, a superoxide ''burst'' will occur which rapidly decreases to baseline level because of the dismutation reaction.…”

“…When a high concentration of H 2 O 2 were added, a step-like current response was observed, proving its selectivity towards O 2 Á-measurement. The present CMC-G-SOD electrode exhibited excellent analytical performance with wider a linear range, high sensitivity, and low response time compared to other studies[38][39][40][41].Lifetime of CMC-G-SOD electrodeThe CMC-G-SOD biosensors were prepared using 4,733 U enzyme. The reproducibility of the amperometric Amperometric response of CMC-G-SOD biosensor for different xanthine concentrations at 650 mV.…”

Sensitive Superoxide Biosensor Based on Silicon Carbide Nanoparticles

“…At 0.25 V applied potential the sensitivity, correlation www.electroanalysis.wiley-vch.de coefficient and detection limit were À 1.375 nA mM À1 , 0.9952 and 2.10 mM, respectively. These analytical parameters are comparable with reported values for other superoxide biosensors [3,6,8,9,12,14].…”

“…Carbon fiber microelectrode modified with electrodeposited gold nanoparticles [6], Au-nanostructures modified electrodes [7 -9], GC electrode modified with carbon nanotubes (CNTs) [10], zinc oxide nanoparticles and nanodisks [11,12], TiO 2 nanoneedles [13] and silica sol-gel matrix at gold nanoparticles modified indium tin oxide electrode [14] have been used for direct voltammetry of SOD and fabrication of third generation of superoxide biosensors.…”

Direct Voltammetry of Copper, Zinc‐Superoxide Dismutase Immobilized onto Electrodeposited Nickel Oxide Nanoparticles: Fabrication of Amperometric Superoxide Biosensor

“…Tian et al developed a third generation biosensor for superoxide based on immobilization SOD on a self assembled monolayer of cystine on gold electrode [10][11][12]. Furthermore, superoxide biosensor based on entrapment of SOD in silica sol-gel matrix have been reported [13,14]. Direct voltammetry of SOD at nafion-cysteine modified gold electrode was also investigated [15].…”