الفهرس 
Literature reviewOnly 14 pages are availabe for public view
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Abstract
This thesis consists of six parts:
Part I: General Introduction
This part is an introduction about food contact materials, types of food packaging, examples of possible leaching contaminants from food packages, leachables under investigation in this study; their potential effects on human health and their limits according to global legislations.
Part II: Literature review
This part includes a description of the chemical and physical properties of the five studied migrants. It also presents a review of the different reported methods for their analysis.
Part III: Novel carbonaceous and carbon nanotubes-based electrodes for determination of Bisphenol A in bottled water and canned food samples using differential pulse voltammetry
In this part, new, rapid, simple and selective voltammetric methods using four different electrodes, namely carbon paste electrode (CPE), disposable pencil graphite electrode (PGE), single-walled and multi-walled carbon nanotubes were developed for determination of Bisphenol A (BPA). The proposed electrodes were fabricated and characterized by scanning electron microscopy. The electrochemical behavior of BPA was thoroughly studied on the surface of the electrodes. The experimental conditions, including effect of pH and effect of scan rate were evaluated and optimized. The results obtained were linear over the following BPA concentration ranges 1.81-6.43, 0.18-0.94, 2.03-4.91 and 0.91-4.91 μg mL-1, with correlation coefficients (r) 0.9996, 0.9997, 0.9995 and 0.9997 for CPE, PGE, SWCNTs and MWCNTs, respectively. The detection limits were evaluated to be 0.10, 0.01, 0.11 and 0.07 μg mL-1, respectively. The methods were satisfactorily applied for the determination of BPA in bottled water and canned food samples purchased from the Egyptian market. The possibility of applying the proposed electrodes to BPA determination in bottled water and canned food samples is demonstrated by the average recoveries of 85.17 -107.04 % and standard deviation less than 7.12 in bottled water samples and less than 6.39 in canned food samples.
Part IV: Chemometrics-assisted methods for simultaneous determination of Bisphenol -A- diglycidyl ether and its reaction products
This part consists of two sections:
Section A: Chemometrics-assisted simultaneous voltammetric determination of Bisphenol -A- diglycidyl ether and its reaction products in bottled water and canned food samples
In this section, chemometrics-assisted voltammetric method using disposable pencil graphite electrode (PGE) was developed for the simultaneous determination of Bisphenol-A-diglycidyl ether (BADGE) and its reaction derivatives, namely BADGE·2HCl, BADGE·HCl·H2O and BADGE·H2O. The experimental conditions were optimized. By adopting partial least squares analysis (PLS-2), we were able to resolve the peak overlap of the investigated compounds. PLS-2 successfully quantified BADGE, BADGE·2HCl, BADGE·HCl·H2O, and BADGE·H2O over the following concentration ranges 0.51-3.15, 1.24-4.44, 1.40-5.00, 0.54-4.54 μg mL-1, respectively. The method was successfully applied to determine the studied compounds in bottled water and canned food samples.
Section B: Chemometrics-assisted spectrophotometric methods for simultaneous determination of Bisphenol -A- diglycidyl ether and its reaction products in canned food samples
In this section, two multivariate calibration methods, namely principal component regression (PCR) and partial least squares (PLS-2) were developed, validated and compared for the simultaneous determination of Bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, including BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl. Chemometrics allowed rapid, accurate and precise simultaneous quantification of the analytes of interest which was not possible by other spectrophotometric methods due to their severe spectral overlap. PCR and PLS-2 based methods quantified BADGE, BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl over the following concentration ranges; 1.40-3.40, 1.00-5.00, 1.00- 4.20 and 1.00-7.00 μg mL-1, respectively. The constructed models were successfully applied for the determination of these compounds in pure form, laboratory prepared mixtures and in various types of canned foods following the limits and regulations of the European Union (EU), where satisfactory recovery results were obtained.
Part V: High-performance liquid chromatographic method for simultaneous determination of Bisphenol-A-diglycidyl ether and some of its reaction products in canned foods using photodiode array detector
In this part, a rapid, sensitive and selective validated HPLC-DAD method was developed for the simultaneous determination of Bisphenol-A-diglycidyl ether (BADGE) and some of its reaction products, namely BADGE·HCl·H2O, BADGE·H2O and BADGE·2HCl in pure form and canned foods where canned beans and tuna were used as representatives of aqueous and oil-in-water food matrices, respectively.
The HPLC conditions were optimized, the best separation was achieved in gradient elution mode of acetonitrile: water using Synergi Hydro RP C18 column. Matrix-matched calibration curves were prepared in canned beans and canned tuna to eliminate the matrix effects.
The proposed method had a linear range of 0.01-0.5 μg g-1 for BADGE·HCl·H2O, BADGE·H2O, and BADGE·2HCl and 0.02-0.70 μg g-1 for BADGE in aqueous food matrices. In oil-in-water based matrices, the proposed method was proven to be sensitive over a linear range of 0.01-0.50 μg g-1 for BADGE·HCl·H2O, BADGE·H2O and 0.02-0.70 μg g-1 for BADGE.2HCl and BADGE. The limits of detection (LOD) and quantification (LOQ) ranged from 0.24-4.6 ng g-1 and 0.73-14.07 ng g-1, respectively. Excellent intraday (n=9) and interday precision (n=9) with RSD% of 0.60-1.55 % and 1.20-3.56 %, respectively. Accuracy was measured at five concentration levels and the recoveries in both matrices ranged from 95.93% to 98.80% with acceptable variation of ± 1.05-2.90 standard deviation.
Part VI: General Discussion
This part includes a comparison between the different proposed methods for determination of the studied compounds and statistical comparison of the results obtained by the proposed methods and the reported methods.
This thesis contains 85 figures, 50 tables and 296 references and ends with an Arabic summary.