Heterolayered Films of Monolayer WS₂ Nanosheets on Monolayer Graphene Embedded in Poly(methyl methacrylate) for Plasmonic Biosensing

Abstract

The interplay between light photons and nanomaterials can give rise to many striking phenomena. Surface plasmon resonance (SPR), which is one such plasmonic sensing mechanism, is gaining much attention from the biomedical fraternity. Two-dimensional (2D) nanomaterials like transition-metal dichalcogenides (TMDCs) and graphenes are recently discovered nanomaterials that have favorable properties like high optical absorption. These materials have been applied extensively in the fields of drug delivery and cancer therapy. However, their applications in the area of plasmonic biosensing need to be explored more. Hence, using commercial SPR sensors, we demonstrate the effectiveness of heterostructured monolayer nanosheets of graphene and WS2 for a plasmonic-based detection system of a specific ligand–analyte interaction between bovine serum albumin (BSA) and anti-BSA. Our detection technique does not require any complex functionalization scheme as the graphene–WS2 nanosheet-coated gold chip can attach protein molecules through hydrophobic interactions. The limit of detection (LOD) obtained for the anti-BSA protein is 0.44 μg/mL.

Near-infrared tunable surface plasmon resonance sensors based on graphene plasmons via electrostatic gating control

“…Graphene-on-gold SPR imaging platform with a ca. 40% sensitivity enhancement was demonstrated experimentally 10 and highly sensitive GEMSPR sensors were used for biological sensing, [11][12][13][14][15] even gas sensing. 16,17 Although GEMSPR sensors can greatly enhance the performance in term of sensitivity comparing with the conventional SPR sensors, their intrinsic refractive index sensing character are still reserved.…”

Improving the Sensitivity of SPR Sensors with Au–Ag alloys and 2D Materials — a Simulation‐Based Approach

“…However, with the recent advancements in the discovery of transition metal dichalcogenides (TMDCs), many researchers used materials such as MoS 2 , WS 2 , and antimonene to design functionalization-free SPR sensors to detect biomolecules like bovine serum albumin (BSA) and micro ribonucleic acid (mi-RNA). [30][31][32][33] An additional advantage associated to the extraordinary properties of these 2D materials is that the optical energy of the incident photons can be transferred more efficiently to generate the SP wave because of the high carrier mobility in some 2D materials, such as Graphene, MoS 2 , and WS 2 which can result in highly sensitive SPR sensors. Moreover, most of the current 2D materials are biocompatible and thus, the risk of structural deterioration and denaturation of biomolecules is greatly reduced.…”

Infrared Polaritonic Biosensors Based on Two-Dimensional Materials

“…As summarized in Figure 1 c, graphene plasmonic polaritons can find promising applications in mid-infrared photonics and optoelectronics, for example, waveguide, filters, optical modulators, photodetection, biochemical sensing and fingerprinting. Recently, there are other newly discovered 2D materials, for example, graphene-dielectric and graphene-metal composites, antimonene, Bi 2 Te 3 , etc., that support similar plasmonic polaritons, which are also potential candidates for these applications [ 61 , 62 , 63 , 64 ]. Recently, phonon-polaritonic biosensors have gained much attention since they possess larger quality factors compared with their plasmonic counterparts.…”