Resin Separation - Hydride Generation - Atomic Fluorescence Spectrometry Determination Of Different Forms Of Arsenic

This thesis aimed at the development of ion exchange resin coupled with hydride generation-atomic fluorescence spectrometry for inorganic arsenic determination and arsenic speciation in food. It consists of the following five chapters.Chapter 1.The first part elaborates the necessity of determination of arsenic compounds in food. Different approaches for the extraction of arsenic species and techniques for speciation of such species are reviewed. The second part introduces the knowledge of ion exchange resin in detail, such as, types, construction, principle, appliance and so on.Chapter 2.The optimization of condition is conducted according to the orthogonal experiment by water-methanol extraction for total arsenic. And the effect of methanol residue on arsenic determination is discussed.Chapter 3.The determination of inorganic arsenic in food is described. The inorganic arsenic is separated by cation exchange resin and determined by hydride generation-atomic fluorescence spectrometry. Besides, the scope of application of food is further discussed.Chapter 4.The determination of inorganic arsenic, monomethylarsenic and dimethylarsenic in food is described. Optimum separations of arsenite, arsenate, monomethylarsonate, dimethylarsinate are achieved by appropriated adjusting pH, eluent concentration and flow rate. The influence of resin processing program to separation is researched. In addition, the effect of hydrogen peroxide on separation is discussed.Chapter 5.The arsenite, arsenate, monomethylarsonate, dimethylarsinate in food is separated by cation exchange resin and anion exchange resin, and determined by Hydride generation atomic fluorescence spectrometry. The separation conditions of dimethylarsinate and arsenite are optimized. Interference and elimination of foreign ions are also discussed.