ABSTRACT
Monitoring of the environment has become a global concern with increasing pollution of surrounding air, water, and soil. Pesticides, toxins, heavy metals, pharmaceutical residues, and water/air/food-borne pathogens are major contributors of environmental contamination. To identify and track the presence of contaminants, numerous analytical approaches have been developed. However, highly sensitive and real-time detection is the need of the hour. Biosensors have been used as quick and inexpensive analytical procedures for this objective. Specifically, impedance-based biosensors are fast, easy-to-use, and portable systems capable of efficient analyte screening in soil, air, and water samples. Electrochemical impedance spectroscopy (EIS) sensors work through the application of a sinusoidal AC excitation potential of small amplitude to the working electrode and recording the resulting current response. The corresponding impedance and phase shift is used to deduce important information about the target analyte. There are some drawbacks associated with EIS sensors relating to selectivity, repeatability, and stability.
This chapter will be mainly dealing with impedance-based detection techniques applied to air, water, soil monitoring, and quantification of pathogenic bacteria.
