Graphene-Based Materials for Biosensors: A Review

Abstract

The advantages conferred by the physical, optical and electrochemical properties of graphene-based nanomaterials have contributed to the current variety of ultrasensitive and selective biosensor devices. In this review, we present the points of view on the intrinsic properties of graphene and its surface engineering concerned with the transduction mechanisms in biosensing applications. We explain practical synthesis techniques along with prospective properties of the graphene-based materials, which include the pristine graphene and functionalized graphene (i.e., graphene oxide (GO), reduced graphene oxide (RGO) and graphene quantum dot (GQD). The biosensing mechanisms based on the utilization of the charge interactions with biomolecules and/or nanoparticle interactions and sensing platforms are also discussed, and the importance of surface functionalization in recent up-to-date biosensors for biological and medical applications.

Keywords: bioimaging; biosensor devices; electrochemical; field-effect transistor; functionalized graphene; graphene; instrumentation; surface plasmon resonance.

Figure 1

Schematic illustration of a typical biosensor system.

Figure 2

Structures of graphene-based materials show (a) the pristine graphene (pure-arranged carbon atoms) with sp²-hybridized carbon atoms, and the chemically modified graphene, including (b) graphene oxide (GO); (c) reduced graphene oxide (RGO) and (d) graphene quantum dot (GQD).

Figure 3

Several techniques of graphene synthesis: (a) graphene sheet is left on top of a silicon oxide wafer exfoliated by scotch-tape technique, its electronic band structure, and the real monolayer and bilayer graphene (Reprinted with permission from [39]); (b) Large scale process of graphene growth using (chemical vapor deposition) CVD and the transferred graphene to poly(methyl methacrylate) (PMMA) (reprinted with permission from [40]); (c) Liquid exfoliation of graphene showing crystalline honeycomb pattern on the exfoliated layer (reprinted with permission from [41]); and (d) epitaxial graphene growth on a silicon carbide (SiC) by sublimation of Si atoms and the structural characteristic of the monolayer graphene (reprinted with permission from [42]).

Figure 4

Schematic structure of chemical synthesis based on Lerf-Klinowski model.

Figure 5

Schematic illustration and photoluminescent mechanism of carbon-based dots, including graphene quantum dot (GQD), carbon quantum dot (CQD), carbon nanodot (CND), compared to the quantum dots made of semiconductor (SQD).

Figure 6

Schematic illustration of the graphene-based materials that can be immobilized with biomolecules as the receptor.

Figure 7

Schematic illustrations of graphene-based biosensors: (a) Pb²⁺ in blood biosensor based on GFET (reprinted with permission from [49]); (b) Pb²⁺ biosensor based on graphene/DNA (reprinted with permission from [109]); (c) CEA protein biosensor based on graphene/anti-CEA (reprinted with permission from [108]); (d) real-time binding kinetics and affinity of DNA hybridization based on GFET (reprinted with permission from [50]); (e) paper-based biosensor for human papillomavirus (HPV) detection (reprinted with permission from [127]); and (f) a lipid-based modified graphene electrochemical biosensor (reprinted with permission from [135]).

Figure 8

Schematic illustration of functionalized graphene-based biosensors: (a) a glucose detection based on GO FET (reprinted with permission from [111]); (b) DNA detection based on printing GO/pentacene FET (reprinted with permission from [110]); (c) urea platform biosensor based on Urease/PEI/RGO FET (reprinted with permission from [112]); (d) Heart failure detection based on Pt NPS/RGO FET (reprinted with permission from [113]); (e) Biotin-SA/GO SPR chip (reprinted with permission from [114]); (f) BSA biosensor based on GO-COOH enhanced SPR (reprinted with permission from [117]); (g) rabbit IgG detection based on RGO SPR (reprinted with permission from [116]); and (h) FRET biosensor based on GQD-PEG aptamer/MoS₂ (reprinted with permission from [23]).