| Two sections are included in this thesis.One was the review,and theother was the research work.In the first part,the applications of some inorganic oxidantsin Chemiluminescence(CL) analysis are reviewed.The focus of the part is to summarizethe analytical application.In the second part, it was found that, by adjusting oxidationability of oxidants such as hypobromite,ferricyanide and periodate,the oxidation abilityof the oxidants can be easily controlled and presented the better analytical performancesin CL analysis.Moreover, the experimental conditions of the CL reactions wereoptimized and the feasibility of applicatipn of the present reactions to the determinationof hydrazine,sulfide and ascorbic acid was evaluated.For the first time, sensitive CLmethods for the detection hydrazine,sulfide and ascorbic acid based on potentialadjustment technique and flow-injection chemiluminescence has been developed.Potential adjustment technique is a promising alternative approach for the improvementof the sensitivity of CL analysis.CL analysis method has its advantages of high sensitivity, rapid analytical speed,wide linear range, simplicity and low cost of instrumentation, suitable for automationand has been successfully applied in life science, material science,clinical medicine andenvironmental monitoring, etc.As we know, chemiluminescence is probably bestdescribed as the emission of light by molecules that are electronically excited by virtueof their precursor' participation in a highly exergonic chemical reaction, almostinvariably an oxidation-reduction reaction, generally, the nature of chemiluminescentreactions is oxidation-redution reactions.So, the analytical performances of CL systemsare closely related to the characteristics of oxidation-reduction reactions. Generallyspeaking, great efforts have been made to improve the sensitivity of CL analysis byadjusting the oxidation ability of oxidants, mainly from three aspects. Firstly. manyideas of on-line electrogenerating nascent state CL reagent were devoted to improve thesensitivity of the CL analysis. Secondly, exploiting and using some new oxidants as CLoxidants can also obtain better analytical performances. Thirdly, adjusting the medium(solvent and PH) of oxidation-reduction reactions could improve the oxidation ability of oxidants in the open literature, and the CL signal could be enhanced greatly, whichfinally resulted in the increased sensitivity.However, up to now, none of the reportsconcems the use of the potential adjustment technique to improve the analyticalperformance of CL analysis.Consideration of the nature of chemiluminescent reactions,we successfully usepotential adjustment technique to improve the analytical performance of the oxidants inCL analysis. Represented by the CL systems such as hydrazine- hypobromite-fluorescein.and luminol-ferricyanide CL system, sensitive CL methods based onpotential adjustment technique and flow-injection chemiluminescence has beendeveloped. Our actual research work includes the following aspects:Firstly, a rapid and sensitive flow-injection chemiluminescence method for thedetermination of hydrazine is described. The method is based on the strongchemiluminescence signal generated from the oxidation of hydrazine by hypobromite inalkaline medium and in the presence of both bromide and fluorescein. In the optimumexperimental conditions, the proposed CL method for hydrazine offered the linear rangeof determination is 3.0×10-5-4.0×10-8g.mL-1 with the relative standard deviation of 1.3%(C=8.0×10-7g.mL-1, n=11) and the detection limit is 1×10-8g.mL-1(3σ). Therecommended method has been successfully used for analysis of lake water sampleswith satisfactory results.Secondly, ferricyanide can react with luminol to produce weak CL in alkalinesolution,and the CL reaction can be catalyzed by sulfide. It was found that, by adjustingthe ratio of c(ferrocyanide) to c(ferricyanide), the oxidation ability of ferricyanide canbe easily controlled and presented the better analytical performances in theluminol-ferricyanide CL system. The experiment shows that the sensitivity of the CLmethod was improved greatly and low detection limit was obtained. Based on thesefindings, a sensitive flow-injection CL method for sulfide was developed. In theoptimum analytical conditions, the proposed CL method for sulfide offered the linearrange of determination is 3.6×10-6-1.2×10-8 mol.L-1 with the relative standard deviationof 2.7% for 1.0×10-7 mol.L-1 sulfide (n=11).and the detection limit is 6×10-9 mol.L-1.The recommended method has been successfully used for analysis of lake watersamples with satisfactory results.Thirdly, ascorbic acid can be determined by its enhancement on the light emissionproduced by the oxidation of luminol by potassium periodate in the basic medium. Increase in the sensitivity of the determination was achieved by introducing potassiumpermanganate into the reaction mixture. The proposed procedure described in this paperwas based on its greatly enhancing effect on the luminol-complex oxidants, consistingof periodate and permanganate system.The proposed procedure allows quantitation ofascorbic acid in the range 2.0×10-8 tol.8×10-10g.mL-1with a correlation coefficient of0.9993 (n=5) and relative standard deviation (R.S.D.) of 2.9% (n=11) at 1.0×10-9g.mL-1.The detection limit (3×blank) was 5×10-11g.mL-1 The method is successfully used todetermine in Vitamin C tablets.
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