Carbon Dots and Graphene Quantum Dots in Electrochemical Biosensing

Abstract

Graphene quantum dots (GQDs) and carbon dots (CDs) are among the latest research frontiers in carbon-based nanomaterials. They provide interesting attributes to current electrochemical biosensing due to their intrinsic low toxicity, high solubility in many solvents, excellent electronic properties, robust chemical inertness, large specific surface area, abundant edge sites for functionalization, great biocompatibility, low cost, and versatility, as well as their ability for modification with attractive surface chemistries and other modifiers/nanomaterials. In this review article, the use of GQDs and CDs as signal tags or electrode surface modifiers to develop electrochemical biosensing strategies is critically discussed through the consideration of representative approaches reported in the last five years. The advantages and disadvantages arising from the use of GQDs and CDs in this context are outlined together with the still required work to fulfil the characteristics needed to achieve suitable electrochemical enzymatic and affinity biosensors with applications in the real world.

Applications of Graphene Quantum Dots in Biomedical Sensors

“…This makes them suitable for the development of biosensors [30][31][32][33]. Additionally, they are often used for signal amplification by serving as nanocarriers including electron transfer promoters, nanozymes, detector bioreceptors, electroactive labeling elements, and catalysts [34][35][36][37], hence offering novel strategies for biosensing platforms and their practical applicability. Over the last decade, numerous nanomaterials have been continuously studied and employed as signal-amplifying species such as nanoparticles (NPs) [38][39][40], graphene [41][42][43], nanowires [44], carbon nanotubes (CNTs) [45], magnetic beads [46,47] and quantum dots (QDs) [48,49].…”

Green synthesis, biomedical and biotechnological applications of carbon and graphene quantum dots. A review

“…Carbon and graphene quantum dots exhibit astounding attributes to current electrochemical biosensing because of their remarkable solubility in various solvents, intrinsic low toxicity, high electronic characteristics, strong chemical inertness, large specific surface area, availability of abundant edge sites for functionalization, significant biocompatibility, low cost, and versatility, as well as their ability to be altered with significant surface chemistries including nanostructured materials (Campuzano et al 2019). These quantum dots can be applied as signal tags or electrode surface modifiers to produce electrochemical biosensing (Campuzano et al 2019).…”

Graphene Quantum Dots as Flourishing Nanomaterials for Bio-Imaging, Therapy Development, and Micro-Supercapacitors

“…GQDs exhibit unique fluorescence properties due to quantum confinement effect and possess a non-zero bandgap in the structure. The properties of GQDs can be tuned by modifying the size and shape by affecting the characteristics of their final structure [ 17 , 18 , 19 , 20 ]. Also, they possess peroxidase-like catalytic activity, which favors them in label-free biosensing [ 21 ].…”