Highly sensitive graphene biosensors based on surface plasmon resonance

Abstract

A surface plasmon resonance (SPR) based graphene biosensor is presented. It consists of a graphene sheet coated above a gold thin film, which has been proposed and experimentally fabricated recently [ChemPhysChem 11, 585 (2010)]. The biosensor uses attenuated total reflection (ATR) method to detect the refractive index change near the sensor surface, which is due to the adsorption of biomolecules. Our calculations show that the proposed graphene-on-gold SPR biosensor (with L graphene layers) is (1 + 0.025 L) x gamma (where gamma > 1) times more sensitive than the conventional gold thin film SPR biosensor. The improved sensitivity is due to increased adsorption of biomolecules on graphene (represented by the factor gamma) and the optical property of graphene.

Graphene–MoS2 hybrid nanostructures enhanced surface plasmon resonance biosensors

“…Recent studies have shown that graphene can be used as an enhanced SPR substrate for biosensing applications. There are several advantages for using graphene-based SPR substrate for sensing: i) they are able to induce significantly large field enhancement at the substrate interface; ii) graphene has relatively large surface area (~2630 m 2 g -1 ) thus allowing it to have a better surface contact with the analyte; and iii) graphene surface can selectively detect aromatic compounds through pi-stacking force and this will help one to be able to study challenging experiments such as DNA interaction with proteins at extreme dilute condition [22][23][24]. However, it was reported that graphene-based SPR sensors possessed the highest detection sensitivity when the total number of graphene layers deposited on the metallic SPR sensing substrate (50 nm) is larger than 10.…”

“…However, it was reported that graphene-based SPR sensors possessed the highest detection sensitivity when the total number of graphene layers deposited on the metallic SPR sensing substrate (50 nm) is larger than 10. Even with such thick layers of graphene on the SPR substrate, the sensitivity enhancement factor has only increased from 1.25 to 2, which is considered to be an incremental improvement for the sensitivity of the SPR biosensor [22,[25][26][27][28].…”

Plasmon-polaritons on graphene-metal surface and their use in biosensors

“…We anticipate that graphene can provide new perspectives in plasmonics in three different ways: (1) as a surface which directly supports surface plasmons at infrared frequencies, 14,16,17 (2) as a tunable transparent platform whose optical properties can be tuned by an external electric field, [18][19][20] and (3) as a functional coating for the existing plasmonic devices. [21][22][23][24][25][26] In this paper, we demonstrate an application of graphene in plasmonics as an example for a functional coating. The primary goal of the paper is to understand the plasmonic properties of graphene coated metal surfaces.…”

“…This type of SPR sensors have been proposed before but have not been demonstrated yet. 21,22 Particularly, we studied nonspecific adsorption of a serum albumin protein (BSA, bovine serum albumin) on a graphene layer using a microfluidic device integrated with a graphene functionalized SPR sensor.…”

Plasmas meet plasmonics

“…4e). Examples include Wu et al [189], where a change in biomolecule concentration led to a change in refractive index near the metal surface which leads to change in propagation constant of the SPP which can be measured by attenuated total internal reflection. Commercially available sensors based on SPR such as the BIAcore instrument from Pharmacia have been widely used for a number of decades [190][191][192].…”