The contamination broadly includes organic, inorganic and microbial pollution.
With increasing industrialization, new contaminants are introduced each day.
Water-quality monitoring is challenging due to the unpredictability and complexity
of various pollutants and their concentrations that need to be detected [1]. Thus,
monitoring of water quality used for consumption is important. Water quality issue
can happen broadly in two ways, either the source of water supply is contaminated
or there is some intermittent issue which took place due to some accidental contamination. Proper monitoring of such issues can’t be done by conventional sampling, methods of grab sampling and laboratory testing, instead a regular
monitoring with quick analysis is required [2].
Earlier, manual detection of water contaminants was done in the laboratories,
which required skilled manpower and specific instrumentation. A number of traditional approaches were available to detect contaminants like; multiple fermentation tube technique [3], filtration method [4], DNA amplification [5], fluorescence
in-situ hybridization (FISH) techniques [6], capillary electrophoresis, field-flow
fractionation [7], chromatography [8] and mass spectrometry [9]. Since a long time,
these methods were used and are still used but they proved to be inefficient for
on-site monitoring of contaminants. Traditional approaches of water pollution
detection are cumbersome and time consuming.
Effective water quality monitoring is the need of the hour which includes the
data collection at several locations, at regular intervals to procure data for establishing trends and assessing the current water quality [10–12]. Water quality
monitoring is required to provide timely warning or identification of any potential
hazard to be caused. The current demand for monitoring tools includes: disposable
systems, biocompatible, monitoring multiple analytes, high sensitivity, low cost and
on-site monitoring [13].
With the rising demand for techniques of water pollution detection, a lot of
progressive research is being done in this area to meet the needs. A wide variety of
water quality sensors are available in the literature to detect various contaminants.
Water quality sensors have their origin from late 1990s and from then till date a lot
of technological and material-based advancement has been done. This chapter gives
an overview on recent advancements in techniques like microfluidics, biosensors
and wireless sensor networks for water contaminant (biological and non-biological)
detection. Figure 1 presents the data obtained from Web of Science which informs
about the number of publications over years for water pollutants (the keywords used
for search are the same as presented). It can be observed from Fig. 1 that maximum
research in past five years is done on biosensors for water pollutants followed by
wireless sensor networks. To add to this, after analysing the information, it was
observed that most of the sensors irrespective of the type of sensor, uses nanomaterials in their fabrication to enhance the sensitivity and reliability. This chapter
also discusses the significant limitations of the techniques and provides suggestions
for future development in the water quality monitoring. Also, on the material front,
nanomaterial enabled sensors have received increasing attention from the
researchers owing to their novel properties and promising performance of rapid
detection and reduced analysis time. Therefore, this chapter also summarizes the
278
R. Soni et al.
With increasing industrialization, new contaminants are introduced each day.
Water-quality monitoring is challenging due to the unpredictability and complexity
of various pollutants and their concentrations that need to be detected [1]. Thus,
monitoring of water quality used for consumption is important. Water quality issue
can happen broadly in two ways, either the source of water supply is contaminated
or there is some intermittent issue which took place due to some accidental contamination. Proper monitoring of such issues can’t be done by conventional sampling, methods of grab sampling and laboratory testing, instead a regular
monitoring with quick analysis is required [2].
Earlier, manual detection of water contaminants was done in the laboratories,
which required skilled manpower and specific instrumentation. A number of traditional approaches were available to detect contaminants like; multiple fermentation tube technique [3], filtration method [4], DNA amplification [5], fluorescence
in-situ hybridization (FISH) techniques [6], capillary electrophoresis, field-flow
fractionation [7], chromatography [8] and mass spectrometry [9]. Since a long time,
these methods were used and are still used but they proved to be inefficient for
on-site monitoring of contaminants. Traditional approaches of water pollution
detection are cumbersome and time consuming.
Effective water quality monitoring is the need of the hour which includes the
data collection at several locations, at regular intervals to procure data for establishing trends and assessing the current water quality [10–12]. Water quality
monitoring is required to provide timely warning or identification of any potential
hazard to be caused. The current demand for monitoring tools includes: disposable
systems, biocompatible, monitoring multiple analytes, high sensitivity, low cost and
on-site monitoring [13].
With the rising demand for techniques of water pollution detection, a lot of
progressive research is being done in this area to meet the needs. A wide variety of
water quality sensors are available in the literature to detect various contaminants.
Water quality sensors have their origin from late 1990s and from then till date a lot
of technological and material-based advancement has been done. This chapter gives
an overview on recent advancements in techniques like microfluidics, biosensors
and wireless sensor networks for water contaminant (biological and non-biological)
detection. Figure 1 presents the data obtained from Web of Science which informs
about the number of publications over years for water pollutants (the keywords used
for search are the same as presented). It can be observed from Fig. 1 that maximum
research in past five years is done on biosensors for water pollutants followed by
wireless sensor networks. To add to this, after analysing the information, it was
observed that most of the sensors irrespective of the type of sensor, uses nanomaterials in their fabrication to enhance the sensitivity and reliability. This chapter
also discusses the significant limitations of the techniques and provides suggestions
for future development in the water quality monitoring. Also, on the material front,
nanomaterial enabled sensors have received increasing attention from the
researchers owing to their novel properties and promising performance of rapid
detection and reduced analysis time. Therefore, this chapter also summarizes the
278
R. Soni et al.