PAMAM Dendrimer Modified Reduced Graphene Oxide Postfunctionalized by Horseradish Peroxidase for Biosensing H2O2.

In this chapter, we describe the tethering of horseradish peroxidase (HRP) to reduced graphene oxide (RGO) for sensing H2O2 in serum. To accomplish this, RGO was synthesized through a green route by reducing graphene oxide (GO) prepared by Hummers method with carrot extract. The RGO was then covalently functionalized by electrochemical amination using fourth generation, amine-terminated PAMAM dendrimers. Subsequently, HRP was postfunctionalized through glutaraldehyde linkage. The synthesized RGO and the functionalization steps were well characterized by spectroscopic, microscopic, and electrochemical techniques. The application of HRP tethered RGO was demonstrated for H2O2 sensing in blood serum. This work provides scope for extending this functionalization strategy for other carbonaceous materials as well.

Tactical tuning of the surface and interfacial properties of graphene: A Versatile and rational electrochemical approach.

Designing a versatile and rational method for the tactical tuning of the surface and interfacial properties of graphene is an essential yet challenging task of many scientific areas including health care, sensors, energy, and the environment. A method was designed herein to tackle the challenge and tune the surface and interfacial properties of graphene using a simple electrochemical tethering of arylamines that provides diverse reactive end groups to graphene. This method resulted in the preparation of graphenes with thiol, hydroxy, amine, carboxyl, and sulfonate surface functionalities respectively. X-ray photoelectron spectroscopy, scanning electron microscopy, and cyclic voltammetry were used to study the chemical, morphological, and electrochemical properties of the modified graphenes. The results show the promising scope of the reported method towards the tactical tuning of the surface and interfacial properties of graphene. Also, this method can give fundamental insights of the surface tuning of graphene and its structurally similar materials. Hence, this approach can be used to advantageously tune the surface properties of the other structurally similar nanocarbons and their hybrid materials to make them potential candidates for many applications.