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Printable and Flexible Biosensors

Khairunnisa Amreen and Sanket Goel

Micro-electromechanical systems (MEMS), Microfluidics and Nanoelectronics Lab, Department of

Electrical and Electronics Engineering, Birla Institute of Technology and Science Pilani, Jharkhand, India

CONTENTS

22.1 Introduction......................................................................................................................357

22.1.1 Categories of Biosensors ..................................................................................358

22.1.1.1 Classification Based on Bioreceptor ..............................................358

22.1.1.2 Classification Based on Transducer...............................................360

22.1.1.3 Classification Based on Electron Transfer....................................360

22.1.2 Characterization Techniques ...........................................................................361

22.1.3 Printable and Flexible Biosensor Fabrication ...............................................362

22.2 Printable and Flexible Biosensors’ Applications........................................................363

22.2.1 Application in Health Management ..............................................................363

22.2.2 Application in Energy Harvesting .................................................................366

22.2.3 Applications in Environmental Monitoring .................................................367

22.3 Conclusion and Future Outlook...................................................................................368

References ....................................................................................................................................369

22.1 Introduction

Recently, advances and emerging trends in the fabrication of printable and flexible bio­

sensors have gained substantial attention since these can be employed as point-of-care

testing (POCT) tools. Significant research for developing methods, materials, and ap­

proaches for strategic designing and targeting specific biosensors has taken place [1]. The

advent of biosensors started in 1999 when IUPAC regarded these as efficient analytical tools

for interference mitigated, both qualitative and quantitative detections [2]. A biosensor is an

electro-analytical device comprising of three major components. The first one is a bior­

eceptor, which is a biological element of choice like an antibody, DNA, enzyme, cell, and

aptamer. These act as redox mediators and transfer electrons at electrode/electrolyte

junctions. Various matrices like graphene, carbon nanomaterials, nanorods, nanosheets,

polymers, metal oxides, composites, etc. are employed to either trap or integrate these

bioreceptors in the matrix. The second one is a transducer, whereupon the exposure of

biological redox mediators with analytes, electrochemical reaction corresponding to oxi­

dation or reduction takes place. This leads to changes in parameters like pH, temperature,

and other chemical changes. The transducer captures these reaction signals and converts

them to a measurable electrical response. The third one is the signal processor, which

DOI: 10.1201/9781003263265-22

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