detection of phenols using Tyrosinase-immobilized carbon nanotube. Yu et al. [43]
developed a Dandelion-like copper oxide microspheres decorated with gold
nanoparticle modified biosensor on the specific thymine-Hg
2+ -thymine base pair
for the highly sensitive detection of mercury ions. Atar et al. [44] designed
molecular imprinted nanosensors for detecting organic matters such as triclosan, by
simulating their biological receptors. Nomngongo et al. [45] made a sensor having a
bioreceptor of horseradish peroxidase to detect persistent organic pollutants in
wastewater samples. Yamashita et al. [46] studied an electrochemical biosensor for
the in-situ monitoring of Biological oxygen demand in the wastewater. Biswas et al.
[47] developed an enzyme based biosensor to detect chromium in water. Verma
et al. [48] integrated microfluidics and optical transduction system to develop a
biosensor to monitor lead concentration. Several optical techniques like surface
plasmon resonance [49, 50] and resonant mirror [51] have been used to detect
pathogens. Yildirim et al. [52] developed a portable optical fibre biosensor using a
fluorescently–labeled specific aptamer to detect E-coli O157: an H7 strain in
wastewater samples.
3.2 Microbial Fuel Cell (MFC) as Biosensors
Recently, microbial fuel cell (MFC) has been found to show promising results as a
tool for water quality monitoring [53]. MFC biosensor is an electrochemical
microbial biosensor; it consists of an electrochemical cell with electrodes usually
separated by a membrane [54]. The MFC utilizes microorganisms as a bio-catalyst
for oxidation of organic matter and generate current at the anode, which produces
electrical power, when coupled to the reduction of oxygen occurring at the cathode
[55]. Microorganisms are present on the anodic surface and their metabolic activities are converted into electricity [56].
Zhou et al. [57] have reviewed several MFC based biosensors for water quality
testing. MFC based biosensors have found there use not only for checking dissolved oxygen, biological oxygen demand and chemical oxygen demand but also
considered for identifying and analyzing different organic pollutants in water
samples [57, 58]. Real time chromium monitoring has been demonstrated by [59]
based on the variations in voltage signal via the activity of immobilized electrogenic bacteria. Chouler et al. [60] developed a paper based microbial fuel cell for
detecting bioactive compounds in water.
To be approved as a standard analytical method, more research is required in this
area. Discovery of new microbial consortia with superior electrogenic potential
which enables fast metabolization of wide range of organic materials is required
[58]. Moreover, the integration between microbial electrochemistry and nanotechnology could result in super conductive electrodes which possess improved efficiency; this area has a lot of potential and is yet to be extensively explored. The
researchers should focus on low cost fabrication and simple designs of MFC-based
sensor devices by using inexpensive and reliable electrode and membrane materials.
Emerging Techniques and Materials for Water Pollutants Detection
283
developed a Dandelion-like copper oxide microspheres decorated with gold
nanoparticle modified biosensor on the specific thymine-Hg
2+ -thymine base pair
for the highly sensitive detection of mercury ions. Atar et al. [44] designed
molecular imprinted nanosensors for detecting organic matters such as triclosan, by
simulating their biological receptors. Nomngongo et al. [45] made a sensor having a
bioreceptor of horseradish peroxidase to detect persistent organic pollutants in
wastewater samples. Yamashita et al. [46] studied an electrochemical biosensor for
the in-situ monitoring of Biological oxygen demand in the wastewater. Biswas et al.
[47] developed an enzyme based biosensor to detect chromium in water. Verma
et al. [48] integrated microfluidics and optical transduction system to develop a
biosensor to monitor lead concentration. Several optical techniques like surface
plasmon resonance [49, 50] and resonant mirror [51] have been used to detect
pathogens. Yildirim et al. [52] developed a portable optical fibre biosensor using a
fluorescently–labeled specific aptamer to detect E-coli O157: an H7 strain in
wastewater samples.
3.2 Microbial Fuel Cell (MFC) as Biosensors
Recently, microbial fuel cell (MFC) has been found to show promising results as a
tool for water quality monitoring [53]. MFC biosensor is an electrochemical
microbial biosensor; it consists of an electrochemical cell with electrodes usually
separated by a membrane [54]. The MFC utilizes microorganisms as a bio-catalyst
for oxidation of organic matter and generate current at the anode, which produces
electrical power, when coupled to the reduction of oxygen occurring at the cathode
[55]. Microorganisms are present on the anodic surface and their metabolic activities are converted into electricity [56].
Zhou et al. [57] have reviewed several MFC based biosensors for water quality
testing. MFC based biosensors have found there use not only for checking dissolved oxygen, biological oxygen demand and chemical oxygen demand but also
considered for identifying and analyzing different organic pollutants in water
samples [57, 58]. Real time chromium monitoring has been demonstrated by [59]
based on the variations in voltage signal via the activity of immobilized electrogenic bacteria. Chouler et al. [60] developed a paper based microbial fuel cell for
detecting bioactive compounds in water.
To be approved as a standard analytical method, more research is required in this
area. Discovery of new microbial consortia with superior electrogenic potential
which enables fast metabolization of wide range of organic materials is required
[58]. Moreover, the integration between microbial electrochemistry and nanotechnology could result in super conductive electrodes which possess improved efficiency; this area has a lot of potential and is yet to be extensively explored. The
researchers should focus on low cost fabrication and simple designs of MFC-based
sensor devices by using inexpensive and reliable electrode and membrane materials.
Emerging Techniques and Materials for Water Pollutants Detection
283