issues, etc. Thus, the monitoring, assessment and detection of any kind of changes in
the environmental systems require certain types of devices which can respond to
particular chemical, biochemical and physical stimulus for which they are designed
and result in an output which can be recorded and analyzed. Such types of devices
are known as “Sensors”. Currently technological and scientific advancement has led
to the development of various kinds of sensors, but revolutionary progress in the
field of sensors have been observed with the advancement in nanotechnology, which
deals with the materials and systems in the nanoscale dimensions (10 to 100 nm or
10
À9 m). According to most of the definitions, “Nanosensors” can be defined as
sensors which have at least one of the dimensions less than 100 nm and have the
ability to collect information at nanoscale and convert it to analyzable data.
Nanosensors should not necessarily be devices manufactured at nanoscale but they
can also be large devices which utilize the unique property of nanomaterials to make
nanoscale measurements. Nanomaterials possess unique properties due to their
nanoscale dimensions, they have high ratio of surface area to volume, giving rise
to distinct physical and chemical properties, including, optical, mechanical and
electrical properties different from those of bulk materials. Nanosensors utilize
such unique characteristics of nanoscaled materials due to the ability of these
materials to interact with the surrounding environment at a nanoscale level. Also, in
many cases they have similar dimensions to the analytes of interest and hence can
give information for nanoscale matrices which is far more accurate, and highly
sensitive (Grieshaber et al. 2008) than the information obtained from normal sensors.
Hence, the main advantages of nanosensors over conventional sensors are:• the low energy required for operation due to nanosizes,
• opportunities to design miniaturized and portable sensors,
• high selectivity and sensitivity, low analyte detection limit,
• ease of surface functionalization to design target specific sensors,
• fast response time,
• applications in real time sensing,
• tuneable size dependent properties making them useful for efficient detection of
large variety of samples.
Further, recognizing the natural sensing abilities of many biological systems, the
combination of nanotechnology with biotechnology have resulted in the development of nanobiosensors with rapid response and more enhanced sensitivity and
selectivity (Dubey and Mailapalli 2016).
Nanosensors are used is almost all areas of life. These are present in the systems
we use everyday like on automatic doors, cars, phones, etc., and their applications
range to a wide variety of devices in various industrial, environmental and agricultural fields (Rodrígues-Mozaz et al. 2004) for instance:• In food processing and technology for analysis of food quality and food toxicants.
• For medical applications for designing reliable diagnostic tools and therapeutic
systems, point-of-care devices, measurement of temperature of living cells, etc.
5 Development of Environmental Nanosensors for Detection Monitoring. . .
93
the environmental systems require certain types of devices which can respond to
particular chemical, biochemical and physical stimulus for which they are designed
and result in an output which can be recorded and analyzed. Such types of devices
are known as “Sensors”. Currently technological and scientific advancement has led
to the development of various kinds of sensors, but revolutionary progress in the
field of sensors have been observed with the advancement in nanotechnology, which
deals with the materials and systems in the nanoscale dimensions (10 to 100 nm or
10
À9 m). According to most of the definitions, “Nanosensors” can be defined as
sensors which have at least one of the dimensions less than 100 nm and have the
ability to collect information at nanoscale and convert it to analyzable data.
Nanosensors should not necessarily be devices manufactured at nanoscale but they
can also be large devices which utilize the unique property of nanomaterials to make
nanoscale measurements. Nanomaterials possess unique properties due to their
nanoscale dimensions, they have high ratio of surface area to volume, giving rise
to distinct physical and chemical properties, including, optical, mechanical and
electrical properties different from those of bulk materials. Nanosensors utilize
such unique characteristics of nanoscaled materials due to the ability of these
materials to interact with the surrounding environment at a nanoscale level. Also, in
many cases they have similar dimensions to the analytes of interest and hence can
give information for nanoscale matrices which is far more accurate, and highly
sensitive (Grieshaber et al. 2008) than the information obtained from normal sensors.
Hence, the main advantages of nanosensors over conventional sensors are:• the low energy required for operation due to nanosizes,
• opportunities to design miniaturized and portable sensors,
• high selectivity and sensitivity, low analyte detection limit,
• ease of surface functionalization to design target specific sensors,
• fast response time,
• applications in real time sensing,
• tuneable size dependent properties making them useful for efficient detection of
large variety of samples.
Further, recognizing the natural sensing abilities of many biological systems, the
combination of nanotechnology with biotechnology have resulted in the development of nanobiosensors with rapid response and more enhanced sensitivity and
selectivity (Dubey and Mailapalli 2016).
Nanosensors are used is almost all areas of life. These are present in the systems
we use everyday like on automatic doors, cars, phones, etc., and their applications
range to a wide variety of devices in various industrial, environmental and agricultural fields (Rodrígues-Mozaz et al. 2004) for instance:• In food processing and technology for analysis of food quality and food toxicants.
• For medical applications for designing reliable diagnostic tools and therapeutic
systems, point-of-care devices, measurement of temperature of living cells, etc.
5 Development of Environmental Nanosensors for Detection Monitoring. . .
93