New Materials for the Construction of Electrochemical Biosensors

Abstract

The development of electrochemical sensors has attracted great interest due to these sensors' high sensitivity and selectivity. Here, we present the general concept and the classification of biosensors, their advantages and drawbacks, the main strategies in electrochemical biosensor technology and the materials used in electrochemical sensors, such as electrodes and supporting substrates, materials for improved sensitivity and selectivity, materials for bioreceptor immobilization, and biological recognition elements. Various nanomaterials, such as carbon-based materials carbon nanotubes, graphene, carbon nanoparticles , inorganic and organic nanoparticles magnetic and metal nanoparticles, nanosized clays , conductive and insulating polymers nanosized and nanostructured polymers, molecularly imprinted polymers , and hybrid materials, etc., have been successfully applied for the enhancement of the electroanalytical performance of biosensors and for the immobilization of biorecognition elements. "mong these, due to their unique physiochemical features, carbon-based materials, such as carbon nanotubes and graphenes, have received special attention in recent years, and examples of surface functionalization using various types of nanoparticles are presented. The future trends in sensor research activities and areas of development that are expected to have an impact in biosensor performance, like immobilization techniques, nanotechnology, miniaturization and multisensor array determinations, are also examined.

Fullerenes in Electrochemical Catalytic and Affinity Biosensing: A Review

“…Fullerene is used as a mediator between the recognition site and the electrode in electrochemical biosensors to enhance the rate of electron transfer produced due to the biocatalytic or biochemical reaction of the analyte in contact with the biological element at the recognition site (see Figure 2) Figure 1. Main carbon nanomaterials used in electrochemical (bio)sensors classified by the type of carbon bond and structure: sp 3 -bonded diamond (a) and sp 2 -bonded carbon (b-d); carbon nanotubes (CNT) (1D-structure) (b); fullerene (0D-structure) (c); and, graphene (2D-structure) (d). Reprinted from [2] with permission.…”

“…Carbon nanomaterials cover a broad range of structures: zero-dimensional (fullerenes, diamond clusters), one-dimensional (nanotubes), two-dimensional (graphene), and three-dimensional (nanocrystalline diamond, fullerite) structures [3]. Carbon nanomaterials such as multiwalled carbon nanotubes (MWCNTs) and fullerene (C 60 ) offer great versatility in terms of facile modification by functional groups, high carrier capacity incorporating both hydrophilic and hydrophobic substances, biocompatibility, relatively wide potential window, low background current, electrocatalytic capability for a variety of redox reactions, and high chemical stability [3,4]. This has led to their wide use in recent years for the preparation of electrochemical (bio)sensors, both as electrode modifiers and nanocarriers.…”

“…This has led to their wide use in recent years for the preparation of electrochemical (bio)sensors, both as electrode modifiers and nanocarriers. Main carbon nanomaterials used in electrochemical (bio)sensors classified by the type of carbon bond and structure: sp 3 -bonded diamond (a) and sp 2 -bonded carbon (b-d); carbon nanotubes (CNT) (1D-structure) (b); fullerene (0D-structure) (c); and, graphene (2D-structure) (d). Reprinted from [2] with permission.…”

Amperometric Biosensors for Glucose and Lactate with Applications in Food Analysis: A Brief Review

“…39 The choice of an appropriate immobilisation method is strongly individual and depends on the nature of the enzyme used, transducer type, physicochemical properties of the analyte, and biosensor's operating conditions. 40 Amperometric biosensors can be classified into three categories in accordance with the principle of the response generation: 41 1/ first generation biosensors -the signal corresponds to electrochemical reaction of an active reagent or product, involved in the biochemical transformation of the target compound; they are also called "mediator-less" amperometric biosensors; 2/ second generation biosensors -the response results from the oxidation/reduction of the redox mediator (freely diffusing low molecular weight compound that effectively shuttles electrons between the electrode surface and the enzyme's active centre); 3/ third generation biosensors -the enzyme's active centre has a direct electrical connection to the transducer and the concentration of the analyte is directly proportional to the redox current generated at the polarised electrode. As a general rule, designing electrochemical biosensors requires consideration of both the target analyte and the complexity of the sample in which the analyte has to be quantified.…”

Electronic tongue technology applied to the analysis of grapes and wines

“…Gold nanoparticles-ZnO composite is one of the most widely discussed electrocatalytic materials with high catalytic activity, optical sensitivity, universal biocompatibility and high chemical stability [117]. [119]. Biosensors based on enzymes combine the advantages of classical electrochemical sensors, which provide high sensitivity and crossselectivity, with the typical specificity of the biosensors [120,121].…”