chapter  12
16 Pages

Nanotechnology and Nanofabrication Applications in Chemical Sensing

ByMagnus Willander, Zafar H. Ibupoto

Biosensors are analytical devices with a sensing biological material including microorganisms, antibodies, enzymes, cell receptors, tissues, derived biomaterials, and nally a transducing microsystem. The transducer is the main component in a biosensor that converts biological signal into a measurable electrical signal. The transducer component is comprised of electrochemical, optical, thermometric, magnetic, or piezoelectric material. The biosensors have gotten signicant importance in medical diagnosis, environmental monitoring, genetics, food industry, and defense applications. The high importance of biosensors in the previously mentioned applications can be correlated to their simplicity, high sensitivity, and practical usability for real sample analysis and on spot analysis [1-4]. Leland Clark Jr. known as the pioneer of sensor eld, developed the oxygen electrode in 1956 [1]. Clark provided a solid platform for the engineering of biosensors based on his concept that has been considered signicantly since the opening of oxygen electrode. In 1962, the Clark concept was further extended experimentally by trammelling glucose oxidase on an oxygen electrode through a dialysis membrane, and the glucose concentration was determined with decreased concentration of oxygen [2]. Later in 1967, an independent and an operational enzyme-based electrode for the detection of glucose was developed [3]. A potentiometric urease that immobilized an

CONTENTS

12.1 Introduction ................................................................................................ 323 12.2 Results and Discussions ........................................................................... 326

12.2.1 ZnO Nanorod-Based Selective l-Ascorbic Biosensor ............... 326 12.2.2 ZnO Nanotube-Based Disposable C-Reactive Protein

Biosensor ......................................................................................... 329 12.3 Conclusion ..................................................................................................335 References .............................................................................................................336