Novel Approaches to Enzyme-Based Electrochemical Nanobiosensors

Abstract

Electrochemistry is a genuinely interdisciplinary science that may be used in various physical, chemical, and biological domains. Moreover, using biosensors to quantify biological or biochemical processes is critical in medical, biological, and biotechnological applications. Nowadays, there are several electrochemical biosensors for various healthcare applications, such as for the determination of glucose, lactate, catecholamines, nucleic acid, uric acid, and so on. Enzyme-based analytical techniques rely on detecting the co-substrate or, more precisely, the products of a catalyzed reaction. The glucose oxidase enzyme is generally used in enzyme-based biosensors to measure glucose in tears, blood, etc. Moreover, among all nanomaterials, carbon-based nanomaterials have generally been utilized thanks to the unique properties of carbon. The sensitivity can be up to pM levels using enzyme-based nanobiosensor, and these sensors are very selective, as all enzymes are specific for their substrates. Furthermore, enzyme-based biosensors frequently have fast reaction times, allowing for real-time monitoring and analyses. These biosensors, however, have several drawbacks. Changes in temperature, pH, and other environmental factors can influence the stability and activity of the enzymes, affecting the reliability and repeatability of the readings. Additionally, the cost of the enzymes and their immobilization onto appropriate transducer surfaces might be prohibitively expensive, impeding the large-scale commercialization and widespread use of biosensors. This review discusses the design, detection, and immobilization techniques for enzyme-based electrochemical nanobiosensors, and recent applications in enzyme-based electrochemical studies are evaluated and tabulated.

Immobilization of Enzyme Electrochemical Biosensors and Their Application to Food Bioprocess Monitoring

“…With further research, the interaction between enzymes and different types of nanomaterial-modified surfaces such as metals and their oxides, graphene-related materials, metal–organic frameworks, conductive polymers, carbon nanotubes, etc., has been considered as a new strategy for enzyme immobilization [ 144 , 145 ]. Nanomaterial-modified electrodes can improve the rate and stability of electron transfer for enzyme immobilization, increase the sensitive surface of the sensor to immobilize more enzyme molecules, and have a fast response time due to their high conductivity that facilitates the rapid transfer of electrons from the redox region of the enzyme to the sensor [ 32 , 141 ].…”

An Electroanalytical Enzymeless α-Fe2O3-ZnO Hybrid Nanostructure-Based Sensor for Sensitive Quantification of Nitrite Ions

“…Recent advancements have led to the creation of various nitrite sensors using nanomaterial matrices, which enhance the surface area for the effective immobilization of proteins or enzymes [ 11 , 12 ]. Despite the high performance of enzyme-based sensors, their limitations include cost, instability, and susceptibility to deactivation under chemical or thermal stress, making enzymeless sensing electrodes a promising solution for accurate nitrite detection [ 13 , 14 , 15 ].…”

Disposable Polyaniline/m-Phenylenediamine-Based Electrochemical Lactate Biosensor for Early Sepsis Diagnosis

“…However, achieving a reproducible detection range that is associated with sepsis remains a challenge. To tackle this problem, most research groups have focused on electrode modification through enzyme immobilization [ 16 ]. This approach offers a significant advantage by preserving the biosensor’s stability [ 17 ], thereby enabling its application in the analysis of blood samples that demand high selectivity.…”