Amperometric Biosensors Based on Direct Electron Transfer Enzymes

Abstract

The accurate determination of analyte concentrations with selective, fast, and robust methods is the key for process control, product analysis, environmental compliance, and medical applications. Enzyme-based biosensors meet these requirements to a high degree and can be operated with simple, cost efficient, and easy to use devices. This review focuses on enzymes capable of direct electron transfer (DET) to electrodes and also the electrode materials which can enable or enhance the DET type bioelectrocatalysis. It presents amperometric biosensors for the quantification of important medical, technical, and environmental analytes and it carves out the requirements for enzymes and electrode materials in DET-based third generation biosensors. This review critically surveys enzymes and biosensors for which DET has been reported. Single- or multi-cofactor enzymes featuring copper centers, hemes, FAD, FMN, or PQQ as prosthetic groups as well as fusion enzymes are presented. Nanomaterials, nanostructured electrodes, chemical surface modifications, and protein immobilization strategies are reviewed for their ability to support direct electrochemistry of enzymes. The combination of both biosensor elements—enzymes and electrodes—is evaluated by comparison of substrate specificity, current density, sensitivity, and the range of detection.

Advances in Bioelectrode Design for Developing Electrochemical Biosensors

“…Haem prosthetic group-containing enzymes, e.g., peroxidases, are promising for the application in third generation biosensors. They efficiently catalyze the H 2 O 2 conversion, hence can be used for its detection, and are often used in various electrochemical biosensors as a part of a bienzymatic system in combination with H 2 O 2 -producing enzymes, where peroxidase’s DET ability is exploited. , Among various peroxidases, horseradish, tobacco, peanut, soybean, and sweet potato peroxidases are reported to support DET . Copper-containing oxidases such as laccase and bilirubin oxidases have also demonstrated their ability for DET .…”

Enzymatic Electrochemical/Fluorescent Nanobiosensor for Detection of Small Chemicals

“…By using its inherent redox properties from metal ions in its structure directly, a metalloenzyme can be considered the best candidate as an electrochemical probe for developing electrochemical biosensors. The amperometry technique, such as amperometric I-T measurement and chronoamperometry, is one of the most broadly used electrochemical techniques to develop metalloenzyme-based electrochemical biosensors using the direct electron transfer reactions between the metalloenzyme and target small molecule [ 55 ]. During these electron transfer reactions, the amperometry technique measures the produced or removed electrons directly, and it is normally plotted as stair-like stepwise graph shapes.…”

Ceruloplasmin in flatland: the relationship between enzyme catalytic activity and surface hydrophilicity

“…14,15 The problem of effective immobilization of enzymes with keeping their natural properties on surfaces with different properties is crucial in medicine, biology, and pharmaceutics as well as in food technology, nanobiophotonics and nanobioelectronics. [16][17][18][19][20][21][22][23] The complexity of this is manifested in terms of permanent and stable immobilization of a certain amount of the enzyme, in the maintenance of their natural properties, and most importantly biological activity. Therefore a given enzyme catalyzes only a few of the many possible reactions for a given substrate.…”