| Resonance Rayleigh Scattering (RRS) is a new analytical technology, for its remarkable characteristics of high sensitivity, simple operation and good selectivity, this method brings to more attention and interesting and has been developed rapidly. Many studies shown that when two ions of different charges form ion association complexes by electrostatic force, hydrophobic force or charge transferring effect, RRS and RNLS (resonance nonlinear scattering, such as double frequency (FDS) or second order scattering ( SOS) )can be enhanced and the spectra characteristics can be changed. Now, these methods have been used to determine nucleic acid, protein, amylase and other biological macromolecules, trace amount of metal and its ions (Ag+, Pb2+, Hg2+, Cu2+, Pa2+, et al.) , and non-metal such as selenium and ammonia, furthermore, RRS has been more and more used for the study of nano-particulates and the determination of some Pharmaceuticals.Pharmaceutical analysis is an important part of analytical chemistry, with great significance for clinic. As natural medicine become more and more important, a lot of technologies and methods for the analysis of natural medicine have been proposed. Presently, Resonance rayleigh scattering method has been applied to the determination and study of some natural medicine (tanshinone IIA, berberine hydrochloride, glycyrrhizic acid, et al.) .Our research shown that natural medicine can react with metal ions to form chelate complexes, react with dye molecules and heteropolyacids to form ion-association complexes by electrostatic force, these reactions results in a significant enhancement of RRS, and the changes of others spectra characteristics. The researches have important application prospects and worth to further studies.In this dissertation quercetin, deoxyandrographolide, resveratrol, morin and vincristine are as samples to study the interaction of alkaloids, flavones with metal ions, dye molecules and heteropolyacids, and effect on some chemical reactions by its oxidation and deoxidization ability. Their RRS spectral characteristics, optimum reaction conditions, influencing factors and analytical application have been studied. Some new methods for the determination of these natural medicine have been proposed, furthermore, the reaction mechanism, the reasons of RRS enhanced, the relationships between RRS spectra and absorption spectra and the structure of the ion-association complexes and chelate complexes are discussed.1. A study on the Resonance Rayleigh scattering spectra of the system of Hg(II)-Quercetin Chelate and its analytical applicationA novel method for the determination of trace amounts of quercetin (QT) based on resonance Rayleigh scattering ( RRS ) has been developed. In pH4.8 6.1 Britton-Robinson buffer solution, the quercetin (QT) can react rapidly with Hg( II) to form a complex, which results in a significant enhancement of RRS and an appearance of a new spectrum. The maximum scattering wavelength appears at 320 run while another little peak shows at 450 ran. The optimum conditions of the reaction and the influencing factors have been investigated. The RRS intensity is directly proportional to the concentration of QT in the range of 0.98～7.0μg/mL and its detection limit is 29.5 ng/mL. This result shows that this method has high sensitivity and good selectivity. Finally, this method was applied for determining QT in sophora japonica sample with satisfactory results.2. Resonance Rayleigh Scattering Method for the Determination of Resveratrol with FeCl3-K3[Fe(CN)6]A novel method for the determination of trace amounts of resveratrol based on resonance Rayleigh scattering (RRS) has been studied. In pH 1.8 acetate sodium and hydrochloric acid buffer solution, the reduced production K4[Fe(CN)6] from the reaction between resveratrol and K3[Fe(CN)6] can react with FeCl3 to form Prussian blue, which results in an appearance of a new spectrum and a significant enhancement of RRS. The maximum scattering wavelength appears at 314 nm while another little peak shows at 375 nm. The RRS intensity is directly proportional to the concentration of resveratrol in the range of 0.05～5.0μg/mL and its detection limit is 15 ng/mL. In this experiment, the optimum conditions of the reaction and the influencing factors have been investigated. This result shows that this method has high sensitivity and good selectivity. Finally, this method was applied for determining of resveratrol in grape leaves and Huzhang samples with satisfactory results.3. A study on the Resonance Rayleigh scattering spectra of the interactions of morin with La3+ and its analytical applicationA novel method for the determination of trace amounts of morin based on resonance Rayleigh scattering (RRS) has been studied. In neutral aqueous medium, the morin can react rapidly with La3+to form a complex, which results in a significant enhancement of RRS and an appearance of a new spectrum. The maximum scattering wavelength appears at 368 nm while other three little peaks shows at 290 nm,342 nm and 460 nm. The RRS intensity is directly proportional to the concentration of morin in the range of 0.06～5.0μg/mL and its detection limit is 18.0 ng/mL. The spectral characteristics, the optimum conditions of the reactions, affecting factors and the properties of analytical chemistry and their analytical applications have been investigated. A high sensitive, simple and fast method is proposed to the determination of morin.4. A study on the Resonance Rayleigh scattering spectra of the system of H3PW12O40- vincristine and its analytical applicationIn 1.0mol/L HCl medium, vincristine react with H3PW12O40 to form an ion-association complex, the RRS intensity can be enhanced greatly and the maximum scattering wavelength appears at 315 nm. The RRS intensity is directly proportional to the concentration of vincristine in the range of 0.013～5.0μg/mL and its detection limit is 4.2 ng/mL. The optimum conditions of the reaction, the effect factors, the influence of foreign substances and the reaction mechanism have been investigated, it is shown that this method has high sensitivity. A high sensitive, simple and fast method is proposed to the determination of vincristine.5. Resonance Rayleigh Scattering Method for the Determination of deoxyandrographolide with crystal violetIn pH11.2 BR buffer medium, deoxyandrographolide react with crystal violet to form an ion-association complex after been hydrolyzed, which results in a significant enhancement of RRS and an appearance of a new spectrum. The maximum scattering wavelength appears at 282 nm while another little peak shows at 323 nm. The RRS intensity is directly proportional to the concentration of deoxyandrographolide in the range of 0.07～4.0μg/mL and its detection limit is 20.5 ng/mL. The spectral characteristics, the optimum conditions of the reactions, affecting factors and the properties of analytical chemistry and their analytical applications have been investigated. A high sensitive, simple and fast method is proposed to the determination of deoxyandrographolide.
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