10. The Application of Graphene in Biosensors

Graphene sparks great interest to develop and extend its applications with its excellent mechanical, electrical, chemical, physical properties. Especially, its higher sensitivity and stronger selectivity presents exciting and bright prospects for biomedical detection applications. From 2008, piles of teams set foot to study graphene applications in biosensors and significant progress has been made. Here we will introduce the applications of graphene in the measurements of biological molecules and microorganism, which facilitates the diagnosis of related diseases, such as diabetes, coronary heart disease, arteriosclerosis and especially cancer.

This chapter is composed of five sections. In the first section, we introduce the synthesis properties of graphene, which enables readers to gain a better understanding of the synthesis and properties of graphene and the advantages of graphene for biosensing. The second section mainly depicts photoluminescence and Raman imaging, electrochemical sensors for enzymatic bio-sensing, DNA sensing, and immune-sensing, which can be applied in optical imaging methods. In the third section, the biological quantification of cancer biomarkers and cells will be discussed. Particularly electrochemical methods like voltammetry and amperometry will be the focus in the content. Due to the properties, for example, simplicity, high sensitivity and low-cost, they are generally adopted transducing techniques for the development of graphene, which based sensors for bio-sensing. The fourth section will describe the Luminescence Sensors in cancer detection applications. The detection method of other biomarkers will be presented in the fifth section, including glucose, hydrogen peroxide, L-Cysteine, dopamine, lysozyme etc. In the final section, in order to reach the necessary standards for the early detection of biomarkers by providing reliable information concerning the patient disease stage, the graphene based biosensors must be established and used, which is the major challenge.