ABSTRACT
Graphene is a novel material for electrochemical sensors due to its excellent electrical and chemical properties and printing technology has recently emerged as a low-cost and practical method for fabrication of exible and disposable electronic devices. A combination of both technologies is highly potential for producing low-cost and disposable sensors. In this chapter, printed graphene-based electrochemical sensor technology is succinctly introduced. This technology generally involves the preparation of conductive graphene-based ink or paste, deployment of printing process and the evaluation of printed graphene-based materials for electrochemical detection. First, various types of graphene-based electrochemical sensors including chemical sensors, enzyme-based, and immuno-based biosensors are extensively discussed. Most studies report that graphene exhibits efcient electron transfer and direct electrochemistry of enzymes, leading to high electrochemical sensitivity and specicity toward various kinds of important analytes including redox couples, metal ions, oxidizing/reducing agents, drug constituents, small biomolecules, DNA, and cells. However, most reported graphenebased electrochemical sensors are fabricated by nonprinted deposition methods such as drop/dip coating, which suffer from poor material control and low productivity. Recently, a few printed graphene-based electrochemical sensors including inkjet-printed graphene-PEDOT:PSS and screen-printed graphene electrodes have been demonstrated. The graphenePEDOT/PSS electrode is fabricated by inkjet printing of graphene conductive ink prepared by one-step electrolytic exfoliation from graphite electrode onto plastic or paper substrate whereas the screen-printed graphene electrode is
distinctively produced from graphene paste prepared by mixing chemically reduced graphene oxide powder with cellulose acetate binder. The reported printed graphene-based sensors exhibit promising electrochemical properties with high sensitivity and good reliability suitable for commercial applications. The printed graphene-based electrochemical sensor technology is rapidly growing and will earn great attention in the near future due to increasing demand of low-cost and disposable electrochemical sensors.
