Polypyrrole Nano- and Microsensors and Actuators for Biomedical Applications - Biomaterials Fabrication and Processing - page 367

13

Polypyrrole Nano- and
Microsensors and Actuators
for Biomedical Applications

Yevgeny Berdichevsky and Yu-Hwa Lo

CONTENTS

13.1 Introduction ......................................................................................................................... 368
13.2 Polypyrrole Actuators—Synthesis and Principles of Operation......................................... 369
13.2.1 Introduction ............................................................................................................ 369
13.2.2 Polypyrrole Electrochemistry ................................................................................ 369
13.2.2.1 Electropolymerization of Polypyrrole ................................................... 369
13.2.2.2 Polypyrrole Conductivity ....................................................................... 369
13 2.2.3 Doping of Polypyrrole with DBS Ions................................................... 370
13.2.2.4 Electrochemical Cycling of PPy(DBS).................................................. 370
13.2.2.5 Volume Change Due to Reversible Electrochemical Redox
Reaction of PPy(DBS) ........................................................................... 372
13.2.2.6 Time Response of the Polypyrrole Films .............................................. 373
13.2.3 Actuation of Polypyrrole Microstructures ............................................................. 374
13.2.3.1 Microfabrication of the Polypyrrole Test Lines..................................... 374
13.2.3.2 Measurement of Electrochemically Controlled Thickness
Change of Polypyrrole Test Lines.......................................................... 374
13.2.4 Integration of Polypyrrole Microstructures
with Silicon Devices............................................................................................... 376
13.2.4.1 Fabrication of an Optically Controlled Polypyrrole
Microstructure ....................................................................................... 377
13.2.4.2 Operation of the Device ......................................................................... 377
13.3 Polypyrrole Microactuators ................................................................................................. 378
13.3.1 Bilayer Actuators.................................................................................................... 378
13.3.2 Direct-Mode Polypyrrole-PDMS Microvalve ....................................................... 379
13.3.2.1 Microfabrication of the Active Part of the Microvalve.......................... 380
13.3.2.2 Microfabrication of the Passive Microfl uidic Component..................... 381
13.3.2.3 Microvalve Operation ............................................................................ 382
13.4 Polypyrrole Nanodevices..................................................................................................... 383
13.4.1 Introduction ............................................................................................................ 383
13.4.2

Polypyrrole Nanowire Electropolymerization and Evaluation
of the Electrochemically Controlled Volume Change ........................................... 383
13.4.2.1 Removal of Hollow Region of Synthesized Polypyrrole

Nanowires by Mechanical Lapping ....................................................... 383

13.4.2.2 SEM Evidence of Electrochemically Induced Volume

Change in Polypyrrole Nanowires ......................................................... 384

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