“Green” Prussian Blue Analogues as Peroxidase Mimetics for Amperometric Sensing and Biosensing

Abstract

Prussian blue analogs (PBAs) are well-known artificial enzymes with peroxidase (PO)-like activity. PBAs have a high potential for applications in scientific investigations, industry, ecology and medicine. Being stable and both catalytically and electrochemically active, PBAs are promising in the construction of biosensors and biofuel cells. The “green” synthesis of PO-like PBAs using oxido-reductase flavocytochrome b2 is described in this study. When immobilized on graphite electrodes (GEs), the obtained green-synthesized PBAs or hexacyanoferrates (gHCFs) of transition and noble metals produced amperometric signals in response to H2O2. HCFs of copper, iron, palladium and other metals were synthesized and characterized by structure, size, catalytic properties and electro-mediator activities. The gCuHCF, as the most effective PO mimetic with a flower-like micro/nano superstructure, was used as an H2O2-sensitive platform for the development of a glucose oxidase (GO)-based biosensor. The GO/gCuHCF/GE biosensor exhibited high sensitivity (710 A M−1m−2), a broad linear range and good selectivity when tested on real samples of fruit juices. We propose that the gCuHCF and other gHCFs synthesized via enzymes may be used as artificial POs in amperometric oxidase-based (bio)sensors.

Highly Porous 3D Gold Enhances Sensitivity of Amperometric Biosensors Based on Oxidases and CuCe Nanoparticles

“…NZs possess increased stability and greater availability due to their simpler preparation technologies. Most reported NZs are mainly mimetics of oxidoreductases, including peroxidase (PO) [ 7 , 8 , 9 , 10 , 11 ].…”

Highly Sensitive Amperometric Biosensors Based on Oxidases and CuCe Nanoparticles Coupled with Porous Gold

“…Activities of AO, ArgO, or GO were determined by the rate of hydrogen peroxide formation in reaction with substrate (methanol, Arg, or glucose) as monitored by the peroxidative oxidation of o-dianisidine in the presence of PO and correspondent substrates methanol [18], Arg [15], or glucose [10].…”

“…Many natural enzymes (oxidases) produce H 2 O 2 as a byproduct of their enzymatic reactions, so the detection of a target substrate can be performed by measuring H 2 O 2 generation. Over the last few years, a number of reports have described the application of various PO-like NZs for H 2 O 2 detection using different sensors [10][11][12][13][14]. The main peculiarities of PO-like NZs as catalysts are that they have high stability, sensitivity, and selectivity to H 2 O 2 in extra-wide linear ranges.…”

“…The main peculiarities of PO-like NZs as catalysts are that they have high stability, sensitivity, and selectivity to H 2 O 2 in extra-wide linear ranges. PO-like NZs coupled with natural oxidases are widely used in amperometric oxidase-based biosensors (ABSs) [1][2][3][7][8][9][10].…”

“…In our earlier works, different types of chemically and "green" synthesized PO-like NZs were described [9,10]. Nanoparticles of CuCe (nCuCe) were chosen as effective electroactive PO-mimetics and were characterized using scanning electron microscopy (SEM) coupled with X-ray microanalysis (SEM-XRM) [9,15].…”