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Materials for Organic Bioelectronics

Giuseppe M. Paternò and Guglielmo Lanzani

Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci, Milano, Italy

Center for Nanoscience and Technology, Istituto Italiano di Tecnologia, Via Giovanni Pascoli, Milano,

Italy

CONTENTS

4.1 Introduction..........................................................................................................................53

4.2 Why Organic Materials are Suitable for Bioelectronics ...............................................55

4.3 Conjugated Polymers..........................................................................................................57

4.3.1 Polyaniline ................................................................................................................58

4.3.2 Polypyrrole ...............................................................................................................58

4.3.3 Poly(3,4-Ethylene Dioxythiophene): Polystyrene Sulfonate ............................59

4.3.4 Polythiophene ..........................................................................................................60

4.4 Small Molecules...................................................................................................................61

4.4.1 Conjugated Oligomers............................................................................................62

4.4.2 Organic Dyes and Pigments..................................................................................62

4.4.3 Photoswitches...........................................................................................................63

4.5 Carbon-Based Nanomaterials............................................................................................64

4.5.1 Graphene...................................................................................................................64

4.5.2 Graphene Micro/Nanostructures.........................................................................65

4.6 Perspectives ..........................................................................................................................67

References ......................................................................................................................................68

4.1 Introduction

Bioelectronic materials for abiotic/biotic interfaces are extensively used for triggering and

probing biological processes, ultimately owing to their ability to modulate the polariza­

tion state of cells. This can occur through various physical and chemical phenomena,

usually involving the injection/generation of charges and/or heat, the displacement of

ions, and the occurrence of red-ox reactions. Since Galvani’s early experiments with frog

legs date back to the end of the 17th century, the electrical excitability of biological tissues

has a rich scientific history. In particular, in the last three decades, a wide community

including chemists, physicists, biologists, and engineers steered their attention to the

development of new abiotic/biotic interfaces to realize efficient communication between

biological and electrical signals, with the final aim to build up devices that are fully

biocompatible and conformable. Some recent and important developments in the field of

DOI: 10.1201/9781003263265-4

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