continuous development along with new advancements in technologies for microscopic imaging. Among biosensors, the classical techniques like cell culture, cell
counting, and plating can detect the presence of specific pathogens (Monis and
Giglio 2006; Gracias and McKillip 2004), yet in a longer time period for completion
of the detection process. It is thus certainly necessary to expand the biosensor tools
with easier, sensitive, and rapid detection. In this chapter, we will be focusing on two
major sensors in demand, namely, chemosensors and biosensors, along with their
classifications, advantages, limitations, and interesting recent findings.
10.2 Chemosensors
There is a substantial increase in the design and development of chemosensors in the
last few years. Exposure to various toxic substances, hazardous chemicals, food
additives/adulterants, pesticides, industrial effluents, etc. has imposed the need for
expansion of chemosensors. Parallel advancements in the field of fluorescence/
colorimetric chemosensing have induced the progress of chemosensor research.
Chemosensor design and development has been interdisciplinary including synthesis
of organic/inorganic molecules combined with different analytical techniques. These
are designed to have a high sensitivity and specificity that allow them to interact
selectively with a specific target analyte present in different complex environments
and are used in clinical diagnostics and detection of agricultural, industrial, or
environmental pollutants, making them significant for health and safety of all life
forms.
Chemosensors, like any other sensors, require the generation of a signal on
binding for detection. Selection of a suitable signal transduction method is vital to
achieving success in the sensing process. Commonly employed strategies in
chemosensors include fluorescence, electrochemical, colorimetric, and surface
plasmon resonance (SPR). Every method has its own advantages and disadvantages
based on the requirements to be met, as given below with significant findings.
10.2.1 Fluorescence-Based Chemosensors
Fluorescence is one of the most frequently used signal transduction methods with
promising sensing applications, as it serves as a highly sensitive technique, solely
due to the emission wavelength which is usually longer compared to the excitation
wavelength and the need for low analyte concentrations (>10
À6 M) for signaling. A
fluorescent sensor is more like a molecular machine with the ability to signal the
presence of analytes like ions/molecules. The two main parts required for designing
of fluorescent sensors includes a signaling moiety or the fluorophore and a receptor
that serves as a recognition molecule. The signaling molecule serves as a signal
transducer, which converts the data obtained (recognition event) into an optical
signal response. The recognition moiety is accountable for attachment to an analyte
specifically and selectively in an efficient manner. This binding relies on the ligand
10 Environment Remediation Tools: Chemosensors and Biosensors
269
counting, and plating can detect the presence of specific pathogens (Monis and
Giglio 2006; Gracias and McKillip 2004), yet in a longer time period for completion
of the detection process. It is thus certainly necessary to expand the biosensor tools
with easier, sensitive, and rapid detection. In this chapter, we will be focusing on two
major sensors in demand, namely, chemosensors and biosensors, along with their
classifications, advantages, limitations, and interesting recent findings.
10.2 Chemosensors
There is a substantial increase in the design and development of chemosensors in the
last few years. Exposure to various toxic substances, hazardous chemicals, food
additives/adulterants, pesticides, industrial effluents, etc. has imposed the need for
expansion of chemosensors. Parallel advancements in the field of fluorescence/
colorimetric chemosensing have induced the progress of chemosensor research.
Chemosensor design and development has been interdisciplinary including synthesis
of organic/inorganic molecules combined with different analytical techniques. These
are designed to have a high sensitivity and specificity that allow them to interact
selectively with a specific target analyte present in different complex environments
and are used in clinical diagnostics and detection of agricultural, industrial, or
environmental pollutants, making them significant for health and safety of all life
forms.
Chemosensors, like any other sensors, require the generation of a signal on
binding for detection. Selection of a suitable signal transduction method is vital to
achieving success in the sensing process. Commonly employed strategies in
chemosensors include fluorescence, electrochemical, colorimetric, and surface
plasmon resonance (SPR). Every method has its own advantages and disadvantages
based on the requirements to be met, as given below with significant findings.
10.2.1 Fluorescence-Based Chemosensors
Fluorescence is one of the most frequently used signal transduction methods with
promising sensing applications, as it serves as a highly sensitive technique, solely
due to the emission wavelength which is usually longer compared to the excitation
wavelength and the need for low analyte concentrations (>10
À6 M) for signaling. A
fluorescent sensor is more like a molecular machine with the ability to signal the
presence of analytes like ions/molecules. The two main parts required for designing
of fluorescent sensors includes a signaling moiety or the fluorophore and a receptor
that serves as a recognition molecule. The signaling molecule serves as a signal
transducer, which converts the data obtained (recognition event) into an optical
signal response. The recognition moiety is accountable for attachment to an analyte
specifically and selectively in an efficient manner. This binding relies on the ligand
10 Environment Remediation Tools: Chemosensors and Biosensors
269