Graphene-Based Electrochemical Sensors for Biomolecules

A. Pandikumar, Perumal Rameshkumar, Alagarsamy Pandikumar

• Publisher: Elsevier
• Year: 2018
• Print ISBN:
  9780128153949
• eBook ISBN:
  9780128156391
• Topic: Technology & Engineering
• Subtopic: Materials Science
• Index: Technology & Engineering

Graphene-Based Electrochemical Sensors for Biomolecules presents the latest on these nanomaterials that have gained a lot of attention based on their unique properties of high mechanical flexibility, large surface area, chemical stability, superior electric and thermal conductivities that render them great choices as alternative electrode materials for electrochemical energy storage and sensor applications. The hybridization of graphene with other nanomaterials induces a synergetic effect, leading to the improvement in electrical conductivity, stability and an enhancement of the electrocatalytic activity of the new nanocomposite material. This book discusses the electrochemical determination of a variety of biomolecules using graphene-based nanocomposite materials. Finally, recent progress in the development of electrochemical sensors using graphene-based nanocomposite materials and perspectives on future opportunities in sensor research and development are discussed in detail. - Covers the importance of detecting biomolecules and the application of graphene and its nanocomposite materials in the detection of a wide variety of bioanalytes - Presents easily understood fundamentals of electrochemical sensing systems and the role of graphene-based nanocomposite materials in research and development

Chapter 1

Graphene-Modified Electrochemical Sensors

M. Amal Raj⁎; S. Abraham John^{† ⁎} Department of Chemistry, Loyola College, Chennai, India
^† Department of Chemistry, Centre for Nanoscience and Nanotechnology, The Gandhigram Rural Institute, Dindigul, India

Abstract

In the last decade, remarkable advances in the field of electrochemical sensors based on graphene and its composites have been depicted. Graphene, a new 2D nanomaterial with outstanding physical, chemical, and electrochemical properties, is an efficient electrode material for creating new sensing assays due to its large conductivity, fast heterogeneous electron transfer, and large surface area. Graphene-modified electrodes prepared by different methods have been used for the successful determination of various biomolecules with high sensitivity and selectivity in the past few years. In this chapter, after a brief introduction to the properties, synthetic methods of graphene and its derivatives, and the importance of various biomolecules, the current development on graphene-based electrochemical sensors is discussed. The implications of graphene on the development of modern electrochemical sensors are also discussed. Finally, future prospects on graphene as advanced electrocatalysts are highlighted.

Keywords

Graphene; Biomolecules; Electrocatalysts; Electrode material; Electron transfer

1 Introduction

The development of electrochemical sensors has received a great deal of scientific interest in the past few decades. Due to their high selectivity and sensitivity, researchers have been actively involved in developing cost-effective electrochemical sensors. The recent emergence of nanomaterials and nanotechnology has opened new prospects in designing the nanomaterial-modified electrodes for electrochemical sensor applications. In this respect, efforts have been directed to the modification of electrodes with nanomaterials with controlled assembly onto electrode surfaces for improved bioelectrocatalytic performance [1–7]. Metal/metal oxide nanoparticles, conducting polymers, macrocyclic metal complexes and carbon nanostructures have been widely used as electrode materials [8–11]. Among them, carbon materials are widely used for the design of electrodes used in electroanalytical chemistry because of their relatively wide potential window in aqueous media, low cost, low background current, and relative chemical inertness in most of the electrolyte solutions [12,13]. To date, many carbon nanomaterials including carbon nanotubes (CNTs), fullerenes, diamond, graphite, carbon dots, and graphene have been used for electrode modification. Among these carbon nanostructures, graphene, the mother of all graphitic nanostructures has become an important electrode material due to its conductivity and high surface area [14,15].

2 Electrochemical Sensors

A sensor (also called detector) is a converter that measures a physical quantity and converts it into a signal which can be read by an observer or by an instrument (today mostly electronic). The sensor contains a recognition element that enables the selective response to a particular analyte or a group of analytes, thus minimizing interferences from other sample components [16]. Electrochemical sensors have several advantages as the electrodes can sense the materials that are present within the host without doing any damage to the host system with low detection limit and high specificity. These devices contain a recognition element that selectively produces an electrical signal that is related to the concentration of the analyte being studied. The active sensing material on the electrode should act as a catalyst and catalyze the reaction of the chemical and biochemical compounds to obtain the output signals. The combination of biosensors and electrochemical sensors leads to a new type of sensors called electrochemical biosensors, where the electrochemical methods are applied for the construction and working of a biosensor [17]. Scheme 1 shows the schematic illustration of an electrochemical sensor. Several nanomaterials such as gold nanoparticles (AuNPs), conducting polymers, graphene, platinum nanoparticles, CNTs, metal oxides, and composite materials have been utilized as an electrode material for the determination of variety of biomolecules and toxic chemicals [18–21]. In this section, we restrict ourselves to graphene-modified electrodes and their applications toward the determination of biomolecules such as vitamins, amino acids, neurotransmitters, purine bases, nucleobases, nucleosides, and nucleotides (Fig. 1).

Scheme 1 Schematic illustration of an electrochemical sensor.

Fig. 1 Graphene modified electrodes for the determination of various biomolecules.

3 Importance of Biomolecules

Biomolecules carry out various biological functions such as the transformation of genetic information, regulating the physiological and biological activity because the levels in the body fluids are an indication of various disorders. Before discussing the detection of various biomolecules using graphene-modified electrodes, a brief discussion about the significance of few important biomolecules are given below (Fig. 2).

Fig. 2 Structures of important biomolecules.

The balance between the inhibitory and excitatory neurotransmitters is important to how our body functions [22]. Knowing the levels of a particular neurotransmitter can help to identify an imbalance immediately or prevent problems occurring in the future. Hence, the sensitive determinations of inhibitory neurotransmitters are important from a clinical point of view. Dopamine (DA), epinephrine (EP), and norepinephrine (NE) are neurotransmitters that...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Contributors
• Preface
• Acknowledgments
• Chapter 1: Graphene-Modified Electrochemical Sensors
• Chapter 2: Functionalized Graphene Nanocomposites for Electrochemical Sensors
• Chapter 3: Doped-Graphene Modified Electrochemical Sensors
• Chapter 4: Graphene–Metal Modified Electrochemical Sensors
• Chapter 5: Graphene–Metal Oxide Nanocomposite Modified Electrochemical Sensors
• Chapter 6: Graphene–Metal Chalcogenide Modified Electrochemical Sensors
• Chapter 7: Graphene–Polymer Modified Electrochemical Sensors
• Chapter 8: Graphene–Carbon Nanotubes Modified Electrochemical Sensors
• Chapter 9: Graphene–Carbon Nitride-Based Electrochemical Sensors for Biomolecules
• Chapter 10: Graphene–Clay-Based Hybrid Nanostructures for Electrochemical Sensors and Biosensors
• Chapter 11: Graphene–Metal–Organic Framework-Modified Electrochemical Sensors
• Chapter 12: Graphene Paper-Based Electrochemical Sensors for Biomolecules
• Chapter 13: Graphene-Containing Microfluidic and Chip-Based Sensor Devices for Biomolecules
• Index