الفهرس 
General Introduction and Literature ReviewOnly 14 pages are availabe for public view
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Abstract
This thesis consists of four parts:
Part I: General Introduction and Literature Review
This part consists of two sections:
Section A: General Introduction
This section consists of a general introduction on PIs, their classification, mode of action and toxicity. The regulations and legislations that control their migration from packaging materials in different products and biological fluids, have been also discussed.
Section B: Literature Review
This section includes a detailed review about the selected PIs. It consists of the review of their structures, chemical and physical properties, and the different analytical methods reported in the literature for their determination.
Part II: Spectrophotometric Methods for The Determination of Four Photoinitiators in Intravenous Injection Solution
This part consists of two sections:
Section A: Triple Divisor Combined with Continuous Wavelet Transform Spectrophotometric Method for Determination of Four Photoinitiators in Intravenous Injection Solution
An environmentally evaluated and reliable triple divisor combined with continuous wavelet transform (CWT) spectrophotometric method was established and validated for the concurrent determination of four PIs: Benzophenone, 4-Hydroxyacetophenone, Benzoin, and Diphenyliodonium hexafluorophosphate in intravenous injection solutions. Triple divisor–CWT peak amplitudes were defined at 260.0, 275.8, 262.2 and 231.2 nm over a linear dynamic range of 0.50-13.00, 0.80-10.00, 1.5-30.00 and 1.00-28.00 µg/mL for Benzophenone, 4-Hydroxyacetophenone, Benzoin and Diphenyliodonium hexafluorophosphate, respectively. The greenness of the proposed method was assessed using two green metric tools enclosing Analytical Eco-scale & Analytical Greenness Assessment (AGREE).
Section B: Different Chemometric Procedures for Determination of Four Photoinitiators in Intravenous Injection Solution
Nine environmently evaluated chemometric methods incorporating the application of principal component regression (PCR), orthogonal partial least square (OPLS), ridge regression (RR) and artificial neural networks (ANN) methods along with different variable selections including genetic algorithm (GA-PCR, GA-OPLS and GA-RR) and interval selection (Interval-PCR and Interval-OPLS) were established and validated for the concurrent determination of four PIs: Benzophenone, 4-Hydroxyacetophenone, Benzoin, and Diphenyliodonium hexafluorophosphate in intravenous injection solutions.. Regarding the adopted chemometrics models, a multivariate multifactor experimental design based on the calibration curve range of the studied PIs was considered to construct a calibration set consisting of eighteen mixtures while using seven mixtures for the validation set. The proposed methods were demonstrated to be sensitive, accurate, precise and reproducible throughout the validation process and could be effectively applied for the regular analysis of the cited photoinitiators in intravenous solutions. The greenness of the proposed methods was assessed using two green metric tools enclosing Analytical Eco-scale & Analytical Greenness Assessment (AGREE).
Part III: chromatographic Methods for The Determination of Photoinitiators
This part consists of two sections:
Section A: chromatographic Method for Determination of Photoinitiators in Baby Food, Cereals and Corresponding Packaging Materials
A chromatographic approach was established and validated for the concurrent investigation and estimation of the PIs, 4-Hydroxyacetophenone, Benzophenone, Benzoin, and Ethyl-4-dimethylaminobenzoate, in baby food, cereals and their corresponding packaging materials. The approach was based on the development of an isocratic reversed phase high-performance liquid chromatography (RP-HPLC) coupled to a photodiode array detector, a C18 column stationary phase and a mobile phase comprising acetonitrile and water (95:5, v/v). The adopted method revealed a linear dynamic range of 10.0 – 5000.0 ng/mL in pure form and 20.0-10000.0 ng/mL in food matrix. The limit of detection ranged from 0.93-2.92 ng/mL and 2.81-8.86 ng/mL and the limit of quantitation ranged from 2.46-6.49 ng/mL and 7.44-19.68 ng/mL in pure form and in food matrix, respectively. In agreement with the International Conference on Harmonization (ICH) criteria, the method was proven to be sensitive, accurate, precise and reproducible throughout validation. The obtained results revealed that the proposed approach could be effectively applied for regular analysis of the cited analytes in various types of products and their corresponding packaging materials.
Section B: Bioanalytically Validated chromatographic Method for Determination of Photoinitiators in Saliva in Contact with Baby Bibs, Teethers and Pacifiers
A green, sensitive and rapid RP-HPLC method was developed and bioanalytically validated to determine and quantify the four PIs, 4-Hydroxyacetophenone, Benzophenone, Benzoin, and Ethyl-4-dimethylaminobenzoate, in saliva in contact with bibs, teethers, and pacifiers. C18 column was used as the stationary phase, acetonitrile and water were used as the mobile phase in an isocratic mode and diode-array as the detector. The method reached a lower limit of quantitation (LLOQ) of 10.00 ng/mL with excellent accuracy and precision. The method was bioanalytically validated according to FDA guidelines and the greenness of the method was evaluated using three tools including the analytical eco-scale, the analytical greenness assessment (AGREE), and the HPLC environmental assessment tool (HPLC-EAT).
Part IV. Electrochemical Determination of Photoinitiators in Dental Products and Saliva
This part consists of three sections:
Section A: selective Glassy Carbon and Gold Wire Electrodes Modified with Bovine Serum Albumin and Gold Nanoparticles for Voltammetric Determination of Camphorquinone in Dental Products and Saliva
In this section, new, rapid, simple and selective voltammetric method using five different electrodes, namely Glassy carbon electrode (GCE), GCE modified with gold nanoparticles (GCE-AuNPs), Gold wire electrode (GW), Gold wire modified with bovine serum albumin (GW-BSA): and Gold wire modified with bovine serum albumin and gold nanoparticles (GW-BSA-AuNPs) was developed for the determination of Camphorquinone (CQ). The experimental conditions, including effect of pH and scan rate were evaluated and optimized. The regression obtained were linear over the following CQ concentration ranges 1.00 x 10-6 – 1.00 x 10-2, 1.00 x 10-9 – 1.00 x 10-2, 1.00 x 10-6 – 1.00 x 10-3, 1.00 x 10-7 – 1.00 x 10-3 and 1.00 x 10-8 – 1.00 x 10-3 M at GCE, GCE-AuNPs, GW, GW-BSA and GW-BSA-AuNPs, respectively.
The detection limits were evaluated to be 2.32 x 10-7, 2.03 x 10-10, 1.69 x 10-7, 3.25 x 10-8 and 3.01 x 10-9 M, for GCE, GCE-AuNPs, GW, GW-BSA and GW-BSA-AuNPs, respectively. The methods were validated and adequately applied for the determination of CQ in dental products and saliva. The greenness of the proposed method was assessed using two green metric tools enclosing Analytical Eco-scale & Analytical Greenness Assessment (AGREE).
Section B: Sensitive Sensors Based on Pencil Electrode Modified with selected Nanoparticles and Conductive Polymer for Voltammetric Determination of Camphorquinone in Dental Products and Saliva
In this section, new, rapid, simple and sensitive voltammetric method using four different electrodes, namely Pencil graphite electrode (PGE), Pencil graphite electrode modified with multiwall carbon nanotubes and hydroxynaphthol blue (PGE-MWCNT-HNB), Pencil graphite electrode modified with gold nanoparticles and hydroxynaphthol blue (PGE-AuNPs-HNB) and Pencil graphite electrode modified with multiwall carbon nanotubes, gold nanoparticles and hydroxynaphthol blue PGE-MWCNT-AuNPs-HNB) was developed for the determination of Camphorquinone (CQ). The experimental conditions, including effect of pH and scan rate were evaluated and optimized. The regression obtained were linear over the following CQ concentration ranges, 1.00 x 10-5 - 1.00 x 10-2 M, 1.00 x 10-6 - 1.00 x 10-2 M, 1.00 x 10-10 - 1.00 x 10-3 M and 1.00 x 10-11 - 1.00 x 10-3 M for the PGE, PGE-MWCNT-HNB, PGE-AuNPs-HNB and PGE-MWCNT-AuNPs-HNB electrodes, respectively. The detection limits were evaluated to be 2.57 x 10-6, 3.03 x 10-7, 2.18 x 10-11 and 3.14 x 10-12 M, respectively. The methods were validated and adequately applied for the determination of CQ in dental products and saliva. The greenness of the proposed method was assessed using two green metric tools enclosing Analytical Eco-scale & Analytical Greenness Assessment (AGREE).
Section C: Ion selective Electrodes for The Potentiometric Determination of Diphenyliodonium Hexafluorophosphate in Dental Products and Saliva
Solid contact ion selective potentiometric sensors based on either polyvinyl alcohol (PVA) or multiwall carbon nanotube (MWCNT) as conductive layer were proposed for selective determination of Diphenyliodonium hexafluorophosphate in dental products and saliva. The potentiometric method has many advantages; it is considered a green method, no need for sample extraction, short analysis time, simple and selective.The performance of the proposed sensors was evaluated according to IUPAC recommendation and it was found that they are rapid, stable and has Nernstian slope. Response time, stability, effect of pH, and selectivity of the proposed sensors were studied. The greenness of the proposed method was assessed using two green metric tools enclosing Analytical Eco-scale & Analytical Greenness Assessment (AGREE).
This thesis contains 89 figures, 48 tables and 265 references and ends with an Arabic summary.