الفهرس 
Emerging Contaminants in the environmentOnly 14 pages are availabe for public view
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Abstract
Summary
This thesis consists of five parts:
Part I: General Introduction and literature review:
This part consists of two sections:
Section A: General Introduction:
This part consists of a general introduction on emerging contaminants, their
sources, and different types. The different ways by which the selected emerging
contaminants reach the environment were described showing their toxic and
hazardous effects on all the living organisms. Regulations and intensive
legislations to control water quality have been discussed. Finally, Procedures that
are needed to be followed in order to overcome and control this hazardous issue
have been discussed.
Section B: Literature review:
This part includes a detailed and thorough review of the selected emerging
contaminants, Atenolol, Diclofenac, Carbamazepine and Triclosan. This review
compromises the chemical and physical properties, and various analytical
methods reported in the literature for their determination.
Part II: Spectroscopic methods for the determination of the selected
emerging contaminants in drinking tap water samples:
This part consists of two sections:
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Section A: First derivative synchronous spectrofluorimetric method for the
simultaneous determination of the binary mixture of atenolol (ATN) and
diclofenac (DCF) in drinking tap water samples:
In this section, a green, simple, sensitive, and selective first derivative
synchronous spectrofluorimetric method was proposed for the simultaneous
determination of two emerging contaminants, ATN and DCF, in drinking tap
water samples. Combining both the synchronous fluorescence technique and the
derivative technique have greatly contributed to the higher sensitivity and
selectivity of the proposed method. Furthermore, to achieve an eco-friendly
method, solid phase extraction was carried out as a green extraction step in order
to minimize the use of toxic organic solvents. The proposed method was validated
according to the ICH guidelines and was found to be within the acceptable ranges.
The proposed method was successfully applied for the determination of the
emerging contaminants in drinking tap water samples with high accuracy,
precision, and selectivity. The method was statistically compared with the
validated reported methods in the literature and no statistically significant
difference was found.
Section B: Micellar enhanced spectrofluorimetric method for the
determination of triclosan (TCS) in drinking tap water samples:
In this work, TCS was detected in drinking tap water samples as an emerging
contaminant using a micellar enhanced spectrofluorimetric method. The weak
fluorescence of TCS was strongly enhanced using the anionic surfactant sodium
dodecyl sulfate as a fluorescent enhancer. Using solid phase extraction as a
method of extraction and water as a solvent have greatly contributed to the
greenness of the proposed method. Validation of the proposed method was
performed according to the ICH guidelines and validation parameters were found
to be within the acceptable ranges. Successful determination of the emerging
contaminant in drinking tap water samples was achieved with high accuracy,
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precision, and selectivity. Statistical comparison between the proposed method
and the validated reported method in the literature was performed and no
statistically significant difference was found.
Part III: Potentiometric methods for the determination of a selected
emerging contaminant in different types of environmental drinking water
samples:
This part consists of two sections:
Section A: Three novel microfabricated copper solid-state potentiometric
sensors for the determination of an emerging contaminant, triclosan (TCS),
in different types of environmental drinking water samples:
In this section, three novel microfabricated copper solid-state ion selective
potentiometric sensors were proposed for the selective and sensitive
determination of TCS in various water samples. Using nanotechnology as an
attractive field and macrocyclic compounds with their enhanced supramolecular
recognition have successfully enhanced the electrical performance of the
developed sensors. Furthermore, the microfabrication of the proposed solid
contact ISEs offers several advantages that greatly enhanced the greenness of the
proposed method. No need for sample pretreatment and extraction step which is
highly recommended for environmental analysis. The performance of the three
proposed sensors was evaluated according to the IUPAC recommendations and
It was found that they had rapid, stable, and Nernstian response.
Response time, influence of pH and temperature on the response, selectivity and
stability of the proposed electrodes were studied to determine the optimum
conditions for measurements. Comparative study was carried to figure out the
most optimum sensor with maximum sensitivity and selectivity.
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The method was statistically compared with the validated reported method in the
literature and no significant difference was found.
Section B: Two novel liquid state potentiometric sensors for the
determination of an emerging contaminant, triclosan (TCS), in different
types of environmental drinking water samples:
This section includes the development of two potentiometric liquid state ion
selective electrodes for the selective and sensitive determination of TCS in
different water samples. The greenness of electroanalysis has drawn a great
attention especially in the field of environmental analysis. Modification of the
developed sensors to be applicable for the in-situ environmental monitoring of
emerging contaminants in the environment was carried out. Sensitivity and
selectivity were greatly enhanced upon modifying the inner filling solution of the
developed liquid state electrodes with 2-hydroxy propyl β- cyclodextrin. The
developed sensors required no sample pretreatment or extraction step offering the
advantage of real time monitoring. The IUPAC recommendations were used to
evaluate the performance of the two proposed sensors.
Different factors including the response time, pH and temperature were studied
and optimized to achieve the optimum conditions for measurements. The two
proposed sensors were compared to determine the most optimum sensor with
maximum sensitivity and selectivity.
Statistical comparison with the validated reported method in the literature were
carried out and no significant difference was found.
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Part IV: chromatographic methods for the determination of the selected
emerging contaminants in environmental water samples:
This part consists of two sections:
Section A: HPLC/DAD method for the determination of a ternary mixture
of diclofenac (DCF), carbamazepine (CBZ) and triclosan (TCS) in
environmental water samples:
In this section, three emerging contaminants, DCF, CBZ and TCS were
successfully determined in water samples using an ecofriendly HPLC/DAD
method. Separation was carried out on reversed-phase C18 column using photodiode
array detector for the simultaneous separation and determination of the
studied analytes in environmental water samples using ethanol/water as a mobile
phase in an isocratic mode. Ethanol was employed as a benign organic modifier
instead of methanol and acetonitrile. The chromatographic conditions were
optimized in terms of mobile phase composition and ratio and flow rate. A green
extraction step was carried out using solid phase extraction minimizing the use of
toxic organic solvents. The proposed method was validated according to the ICH
guidelines and was found to be valid. System suitability parameters were
calculated and were found to be within the accepted ranges. The method was
statistically compared with the validated reported methods in the literature and
no significant difference was found.
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Section B: UPLC-MS/MS method for the determination of a ternary mixture
of atenolol (ATN), diclofenac (DCF) and carbamazepine (CBZ) in Nile river
water:
In this section, a UPLC-MS/MS method was proposed for the simultaneous
determination of ATN, DCF and CBZ in Nile river water samples using
acetonitrile/water as a mobile phase in a gradient mode. Samples were collected
from a drinking water treatment plant. Shortening the run time to be only 8
minutes and carrying out solid phase extraction as an eco—friendly extraction
method have enhanced the proposed method greenness. Matrix effect study
showed no significant ionization suppression. Validation of the proposed method
was performed according to the ICH guidelines and assay parameters were within
the acceptable ranges. The high sensitivity and selectivity of the proposed method
have successfully enhanced its application in environmental analysis.
Furthermore, the proposed method exhibits high accuracy and precision. No
significant difference was found between the proposed method and the validated
reported method in the literature upon carrying out a Statistical comparison.
Part V: Greenness assessment and General discussion:
In this part, owing to the significance of green chemistry and the great interest in
implementing green analytical methodologies, greenness assessment of the
proposed methods was scientifically performed using two different evaluation
tools, Eco-scale, and Green analytical procedure index. Furthermore,
comparative study between the greenness of the proposed methods and the
reported methods in literature was performed. An overall evaluation of the
proposed methods was performed, highlighting the major advantages presented
by these methods for each contaminant. A one-way ANOVA was performed
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between the proposed methods and the reported method for each contaminant and
no statistically significant difference was found.
This thesis consists of 68 figures, 45 tables, 577 references