الفهرس 
REVIEW OF LITERATUREOnly 14 pages are availabe for public view
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Abstract
Chapter I contains an introduction to show the direct relationship between several kinds of human diseases and health with specific pollutant when exists in the natural resources. Therefore, it is a challenge for analytical chemist to find out simple, sensitive, less expensive and safe methods for determination of such kinds of environmental pollutants.
Chapter II includes literature review about the phenomenon of pollution, its sources and treatment and classification of pollutants. This has led us to discuss in some details the solid phase extraction technique and it utility in analytical applications to preconcentrate/separate toxic matter with special reference to different kinds of solid sorbents that are commonly used as SPE sorbents such as silica gel, polystyrene-divinylbenzene copolymer and polyurethane foam. In chapter III, the objectives and aims intended from this work have been listed. The experimental part including instrumentations, chemicals and solutions, sample preparations and the recommended procedure is explained in details through chapter IV.
Chapter V contains the results and discussions which consist of two main sections. In the first section (A), silica gel and amberlite XAD-2 were chemically functionalized to get new sorbents capable to preconcentrate/separate trace concentrations from heavy metals (namely Cu, Zn, Pb, Cd and Ni) as an example of inorganic pollutants. Firstly, 2-aminophenol was anchored to the surface of silica gel or resin via azo coupling reaction to give AP-SG or AP-XAD-2 sorbent, respectively. Secondly, the obtained material from the first step was further diazotized and coupled to 2-naphthol, acetylacetone or 1-phenyl-3-methyl-pyrazol-5-one to give HPANaph-SG (or HPANaph-XAD-2), HPAAA-SG (or HPAAA-XAD-2) or HPAPyr-SG (or HPAPyr-XAD-2), respectively. Finally, comparative study among these new SPE sorbents was performed using the static and dynamic procedures in order to investigate the performance of each group of sorbents.
The silica gel modified sorbents have indicated sorption capacity within the range 115 -206, 102-143, 48-76, 65-98 and 112-216 µmol/g for Cu, Zn, Pb, Cd and Ni respectively. The preconcentration factor is 71, 250, 100-200 and 83-167 for 2-aminophenol, 2-naphthol, acetylacetone and pyrazolone derivatives, respectively and the LODs are less than 9.4, 4.5, 3.8 and 4.0 µg l-1, respectively. Certified (NIST 1577b bovine liver) and natural (drinking water) samples were analysed and the results showed RSD from 1.0 -7.4% for three replicate measurements.
The amberlite XAD-2 based sorbents were also studied in details for preconcentration/separation of the same elements. Exchange capacity was found to be in the range 49-81, 44-71, 18-27, 29-40 and 59-85µmol/g for Cu, Zn, Pb, Cd and Ni respectively. The preconcentration factor is 143, 285, 200-267 and 188-250 for 2-aminophenol, 2-naphthol, acetylacetone and pyrazolone derivatives, respectively and the LODs are less than 2.4, 0.9, 2.1 and 3.3 µg l-1, respectively. Analysis of the certified and drinking water samples showed RSD from 1.0 to 8.5%. The HPANaph-SG and HPANaph-XAD-2 are recognized the best sorbents from the whole developed materials since they provide the highest values both in exchange capacity and preconcentration factor. Accordingly, further application of these two sorbents was carried out to analysis of apple leaves and synthetic seawater samples. The results demonstrate good recovery (95– 106 %) and (91-108 %) with RSD (1.6 – 7.4%) and (1.2-7.2%) for HPANaph-SG and HPANaph-XAD-2 sorbents, respectively.
In the second section (B), we have prepared methylene blue grafted polyurethane foam (MB-PUF) as SPE sorbent. The material was successfully applied to preconcentrate/separate organic pollutants (β-antibiotics namely penicillin G, amoxicillin and ampicillin). A flow injection analysis – solid phase extraction (FIA – SPE) procedure with UV detection at 230 nm has been developed using a mincolumn packed with the MB-PUF sorbent. The sorbent has the capability to adsorb anionic organic species such as β - lactam antibiotics (penicillin G, amoxicillin and ampicillin) within the pH range 8-9. The developed procedure showed good preconcentration/separation performance. The proposed sorbent showed capacity 0.046, 0.062 and 0.057 µmol/g, concentration factor 14, 16 and 11 at 2 min preconcentration time and LOD 12, 15 and 19 ng/ml for penicillin G, amoxicillin and ampicillin, respectively. The procedure enables sample frequency 12 h-1. Moreover, the method was applied to analysis of these antibiotics in bovine milk with recovery ≥ 88 % and RSD ≤ 8.8 %. In addition, pharmaceutical formulations were also analyzed by the proposed procedure and the results showed recovery ≥ 92 % and RSD ≤ 8.4 %. Finally, the sorbent showed satisfactory separation efficiency of the three examined antibiotics by using 25 cm MB-PUF column and ammonia buffer pH 7.0 mobile phase at 0.15 ml/min flow rate. Chapter VI demonstrates the conclusions achieved from the whole work and the recommendations for future work that may be a conducted in this area. Chapter VII includes the references utilized in this work.