TABLE OF CONTENTS While the implementation of organic films and chemical nanotechnologies microelectronics and optoelectronics is the subject of ongoing discussions and competitions with solid-state technologies, their major role in the development of chemical and biosensors cannot be argued at all. The enormous variety of organic and bioorganic compounds, and the practically unlimited possibilities of their further chemical synthesis, cannot be compared with the rather limited choices of inorganic materials used in chemical and biosensors.
The role of chemical and biosensors has become extremely important in modern computer-controlled systems, used in such areas as biomedical instrumentation, environmental control systems, and expert systems for food industry and agriculture, where sensors provide an interface between the environment and the computer-controlled systems. The number of publications on chemical and biosensors for the last two decades reaches 10,000, which includes many excellent reviews and monographs [1 23]. This area, however, is still evolving, and this chapter gives a short review of recent developments in sensors, as well as the summary of existing knowledge.
Chemical and biosensors can be defined as devices that transform different chemical or biochemical reactions (including adsorption of molecules) into some measurable physical parameters. A simple scheme of chemical and biosensors comes from the above definition. As shown in Figure 7.1, a typical chemical or biosensor consists of three main parts: (1) a sensitive membrane, where the molecular recognition or chemical reactions occur; (2) a transducer, which serves as...
