| Flavonoids are a kind of natural organic compounds in nature extensively with potential physiological activities and effective components of Herbs,which have less side effect and extensive pharmacology effect. Flavonoids have many biological activities. For example, antibacteria, diminishing inflammation, anti-mutation, lowing blood pressure, curing and preventing cancer and so on. Flavonoids have also been the emphasis of the research all over the world, which are the important aspect in the search of biologically active compounds. Chrysin is one of flavonoids widely spread in nature. In order to research coordination abilities of chrysin with metal ions, chrysin with its transitional metal ion complexes are researched in fluorescence in this paper. All this done is aimed for providing some scientific message for developing of chrysin in analytical application.The rapid determination technology of metal ions in the environment and food has been received a lot of attention in the recent years in analytical research field. Chromium is widely used in industries, such as steel production, leather tanning,painting, dyeing. At the same time, chromium has produced many serious environmental contaminants to human, animals and plants. Therefore, more and more environmental workers in many countries concern about controlling and reducing the environmental pollution caused by chromium. Manganese is an essential microelement of our body, and it has important physiological functions. However, incepting too much manganese can do great harm to our health. It is important to detect trace chromium and manganese in environment and food. There are many methods for determination of chromium and manganese, but a few reports about fluorescence enhancement are available to determinate chromium and manganese.Rapid, simple analysis methods of chromium and manganese have been established on the basis of the fluorescence enhancement effect of chrysin-Cr binary system and chrysin-Cr-Mn ternary system, respectively. The two approaches have achieved the determination of chromium ion in environment water samples and manganese ion in grain. They can be regarded as two effective measures for the determination of this two metal ions and meet the needs of the testing.This paper includes four parts: Chapter One ReviewIn the first section,we generally discuss the classification, biological activities, various physical and chemical characters of flavonoids in this paper. In the second section, the researches which focused on extraction, purification, separation and analysis process of flavonoids are introduced and compared. In the third section, the application of flavonoids is summarized in simplicity. Flavonoids with metal ions complexes are briefly described. The present researches of chrysin and its complexes are introduced in the fourth section. The fifth section summarizes the measures of the metal ions Cr and Mn. At last, the purpose and meaning of this work are discussed. Totally 123 references are cited in the chapter one.Chapter Two Isolation and Structure Identification of a Flavone glycoside from the roof of Przewalskia tangutica MaximA flavone glycoside from the roof of Przewalskia tangutica Maxim has been separated, purified and identified. The flavone glycoside is isolated from glacial acetic acid by making use of silica gel and polyamide column chromatography and other methods of separation, purification. And its structure is inferred as 5, 7 - dihydroxy-flavone glycoside, namely, chrysin glycoside, which is identified by nuclear magnetic resonance (NMR), infrared (IR), mass spectrometry (MS) of modern technologies. It is the first time that the flavone glycoside which can generate CE-ECL response signal is isolated from the root Przewalskia tangutica Maxim.Chapter Three Determination of Trace Total Chromium in Water Samples based on Fluorescence Enhancement effect of Chrysin-Cr (III)complexA new fluorescence method for the determination of trace total chromium in the water samples is proposed based on the fluorescence enhancement effect of chrysin-Cr (Ⅲ) system. In the buffer solution of HAc-NaAc at pH 3.5, Cr(Ⅲ) ion reacts with chrysin by molar ratio 1∶3, and forms a highly fluorescent active complex in the presence of some methanol. The maximum excitation and emission wavelengths of the complex are 260 nm and 429 nm respectively. Under the optimum conditions, the fluorescence intensity at 429 nm increases linearly with the concentration of Cr (Ⅲ) in the range of 0.480 g/L～15.6 g/L, linear regression equation is F =211 +46.0 C ( g/L) with the correlation coefficient of r=0.9993. By means of the pretreatment process reducing Cr(Ⅵ) to Cr(Ⅲ), the total chromium can be determined with the detection limit of 0.216 g/L (3σ). The present method has been applied to the direct determination of total chromium in electroplating waste water, Yellow river and tap water. The recovery is ranged from 97 % to 103% for environmental water samples. This method is sensitive, selective, simple and fast to be performed.Chapter Four Determination of Trace Manganese(Ⅱ) in Grain based on Fluorescence Enhancement effect of Chrysin-Cr(III)-Mn(Ⅱ) ternary complexA new enhancement fluorimetry for the determination of trace Manganese(Ⅱ) in grain samples is developed. In the buffer solution of HAc-NaAc at pH 4.5, chrysin reacts with Cr(Ⅲ) and Mn(Ⅱ) by molar ratio 4∶1∶2, and forms a highly fluorescent active polynuclear ternary complex in the presence of some methanol and surfactant Tween-80. The maximum excitation and emission wavelengths of the ternary complex are 225 nm and 342 nm respectively. Under the optimum conditions, the fluorescence intensity at 342 nm increases linearly with the concentration of Mn(Ⅱ) in the range of 0.396 g/L ~ 16.2 g/L, linear regression equation: F=298+40.4C ( g/L) with the correlation coefficient of r= 0.9990. The detection limit of analytical method is 0.352 g/L (3σ). The method has the advantages of simplicity, high sensitivity and fast speed, and has been successfully applied to the determination of trace Mn (Ⅱ) in grain samples with satisfactory results. The real sample recovery is ranged from 97.8% to 103.8%.
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