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We describe a fundamental study on the plasmonic properties and advanced biosensing mechanisms of functionalized graphene. We discuss a specific design using modified carboxyl groups, which can modulate surface plasmon (SP) coupling and provide an advantage for their binding to the sensing layer with high-performance affinity in an immunological reaction. The functionalized graphene-based surface plasmon resonance (SPR) biosensors have three advantages: high performance, high sensitivity, and excellent molecular kinetic response. In the future, functionalized graphene sheets will make a unique contribution to photonic and SPR diagnosis devices. We wish to highlight the essential characteristics of functionalized graphene-based SPR biosensors to assist researchers in developing and advancing suitable biosensors for unique applications.

We present a surface plasmon resonance real-time detection method to monitor the deoxidized process of graphene oxide converted to reduced graphene oxide by electrochemistry. This may pave the way to new development in rGO-based application, like biosensor, gas sensor and photoelectric devices.

Plasmonic emissions generated by excitation of an organic layer on a metal grating structure are demonstrated. The emissions correspond to the resonant condition of surface plasmon (SP) modes on the Alq(3)/Au interface, and the grating structure is coupled to the Au/air interface to provide light emissions. Experimental variations in pitch to control plasmonic bandgap obtained highly directional plasmonic emissions with enhanced intensity. This method is readily applicable for detecting refractive index changes by using SP-coupled fluorophores to obtain emissions of varying wavelengths and viewing angles. The calculations showed that the wavelength of the plasmonic emitter changed from 480 to 680 nm at certain viewing angles, while the concentration of contacting glucose increased from 10% to 40%. Accordingly, a device with a pitch size of 500 nm had a sensitivity of Δθe/Δn=37.76° and Δn/Δ=1.681×10(-4) RIU (refractive index unit). Therefore, the proposed approach has potential applications in low-cost, disposable, point-of-care biosensors.

In this paper, we report the enhanced performance of Graphene-Nafion-GOD based enzymatic biosensors to detection glucose used fast, simple, and easy to control fabrication method. These materials are prepared by mixing graphene, a Nafion perfluorinated resin, and glucose oxidase (GOD) in appropriate amounts. The graphene has a diameter of 8 μm. As a result, the sensitivity of lower GOD concentration is two times the higher concentration. It can be seen that the sensitivity was enhanced by graphene. The sensor was characterized electrochemically using cyclic voltammetry and amperometry in the presence of hydrogen peroxide and glucose.

This paper is intended to demonstrate a facile and effective method to construct single layer graphene films onto the self-assembled monolayer (SAM) at Au electrodes based surface plasmon resonance (SPR) biochips integrated loop-mediated isothermal amplification (LAMP) for tuberculosis bacillus (TB) detection. It is a novel Au-SAM-graphene nanocomposites and taking advantages of the striking properties of both graphene and Au film, fundamental understanding in hybrid material manipulation and new electrochemical properties can be obtained. The sensitivity of TB detection in the LAMP-based assay for the amplification of the Insertion Sequence 6110 (IS6110) samples was determined by a single-layer graphene/Au thin film and compared with that of a conventional Au/Cr-based SPR chips. The results show that a graphene/Au SPR offers a potentially powerful assay, with a highly sensitive analysis, that may be applicable as an important tool for bio-marker detection.