Recent trends in carbon nanomaterial-based electrochemical sensors for biomolecules: A review

Abstract

Carbon nanomaterials are advantageous for electrochemical sensors because they increase the electroactive surface area, enhance electron transfer, and promote adsorption of molecules. Carbon nanotubes (CNTs) have been incorporated into electrochemical sensors for biomolecules and strategies have included the traditional dip coating and drop casting methods, direct growth of CNTs on electrodes and the use of CNT fibers and yarns made exclusively of CNTs. Recent research has also focused on utilizing many new types of carbon nanomaterials beyond CNTs. Forms of graphene are now increasingly popular for sensors including reduced graphene oxide, carbon nanohorns, graphene nanofoams, graphene nanorods, and graphene nanoflowers. In this review, we compare different carbon nanomaterial strategies for creating electrochemical sensors for biomolecules. Analytes covered include neurotransmitters and neurochemicals, such as dopamine, ascorbic acid, and serotonin; hydrogen peroxide; proteins, such as biomarkers; and DNA. The review also addresses enzyme-based electrodes that are used to detect non-electroactive species such as glucose, alcohols, and proteins. Finally, we analyze some of the future directions for the field, pointing out gaps in fundamental understanding of electron transfer to carbon nanomaterials and the need for more practical implementation of sensors.

Adsorption of Bovine Serum Albumin on Carbon-Based Materials

“…BSA solutions were prepared in phosphate-buffered saline, PBS (pH 7.2). Kinetic studies were conducted with BSA solutions (1 mg/mL) at varying adsorption times (5,10,20,30, 60 and 90 min) at room temperature while shaking at 150 rpm. Prior to BSA adsorption, expanded graphite (~100 mg) was equilibrated overnight in PBS (2.0 mL) to prevent adsorption of environmental contaminants from the air and then the excessive liquid phase was separated by centrifugation.…”

“…Development of novel nanostructured carbons and methods for their surface modification expanded the choice of materials and led to the applications in biosensors, coatings for medical devices, drug and gene delivery carriers and bioimaging [3]. Current interest to biomedical applications of novel nanostructured carbon materials is based on their structural, mechanical, physical and chemical properties, which are often superior to other materials [4,5]. This interest is supported by the fact that many carbon materials have good biocompatibility and can be used in direct contact with blood and human tissues [6].…”

Nanomedicine: A New Approach for Treatment Neuropsychiatric Diseases

“…Researchers have found that ferric hydroxide-Nafion film-coated carboxylic acid-modified carbon nanotubes changed dopamine in drosophila [40]. Functionalization of carbon nanotubes with poly (diallyl dimethylammonium chloride) (PDDA) reduced the detection limit of dopamine [41] .…”

Diagnosis and Treatment of Neurological and Ischemic Disorders Employing Carbon Nanotube Technology

“…Functionalized CNT electrodes have been used for neurotransmitter detection with high sensitivity and selectivity. Vertically aligned CNTs can lead to more reproducible surfaces with CNT ends exposed to enhance sensitivity [84]. CNT yarns are made of multiple CNT fibres twisted together and these have been utilized by Yang and team for production of CNT yarn microelectrodes (CNTYMEs).…”