Conductance modulation of charged lipid bilayer using electrolyte-gated graphene-field effect transistor.

Mohammad Javad Kiani,Mohammad Taghi Ahmadi,Meisam Rahmani,Moslem Zare,Mahdi Saeidmanesh,Fauzan Khairi Che Harun

doi:10.1186/1556-276x-9-371

Abstract

Graphene is an attention-grabbing material in electronics, physics, chemistry, and even biology because of its unique properties such as high surface-area-to-volume ratio. Also, the ability of graphene-based materials to continuously tune charge carriers from holes to electrons makes them promising for biological applications, especially in lipid bilayer-based sensors. Furthermore, changes in charged lipid membrane properties can be electrically detected by a graphene-based electrolyte-gated graphene field effect transistor (GFET). In this paper, a monolayer graphene-based GFET with a focus on the conductance variation caused by membrane electric charges and thickness is studied. Monolayer graphene conductance as an electrical detection platform is suggested for neutral, negative, and positive electric-charged membrane. The electric charge and thickness of the lipid bilayer (QLP and LLP) as a function of carrier density are proposed, and the control parameters are defined. Finally, the proposed analytical model is compared with experimental data which indicates good overall agreement.

Highlights

Graphene is a monolayer of sp2-bonded carbon atoms, and this sp2 bond makes the graphene structure look like honeycomb crystal, as shown in Figure 1 [1]
A monolayer graphene-based graphene field effect transistor (GFET) with a focus on the conductance variation caused by membrane electric charges and thickness is studied
The focus of the present paper is to demonstrate a new model for GFET to measure changes in the membrane's electric charge and thickness

Summary

Background

Graphene is a monolayer of sp2-bonded carbon atoms, and this sp bond makes the graphene structure look like honeycomb crystal, as shown in Figure 1 [1]. This means that GLP is considered to be a function of electric charge (QLP) as follows. The proposed model, coupled with the experimental data, is shown in this work to confirm that the conductivity of the graphene-based biosensor is changed by the electric charge and membrane thickness of the lipid bilayer. 0.045 biomimetic membranes of different thicknesses, a significant shift in Vg,min of the ambipolar FET occurs due to the electronic devices on both the n-doping and p-doping materials

Conclusion

Ruoff R: Graphene