| The present thesis described the basic principles and the application of chemluminescence in analytical chemistry. It consisted two parts:Part â… A review of chemiluminescence analysisIn 1877, Radziszewasi, using lophine (2,4,5-triphenylimidazole), found that synthetic compounds could produce luminescence. Since then, numerous compounds have been synthesized and their chemiluminescent reaction mechanisms and applications to analytical chemistry studied. Recently, chemiluminescent systems have been proven to be valuable for trace analysis. The most characteristic property of a chemiluminescent system for analytical use is its remarkable sensitivity. Certain compounds can be detected in the range from femtomole to atomole levels. Therefore, as an alternative to radiometric analysis, interest in chemiluminescent systems has focused on their utility for the determination of trace amounts of organic compounds in biomaterials and in environmental samples.In this part, based on the fundamental theory of chemiluminescence and several common reactions of chemiluminescence, especially luminol chemiluminescence system, the applications of various chemiluminescent detection methods in the pharmaceutical and environmental analysis were described, using more than 280 references concerning chemiluminescence analysis during 2000~2005 year.Part â…¡ Research reportsLuminol as one of the most important and familiar chemiluminescent compounds, its chemiluminescent mechanism had been extensively studied, since its chemiluminescence(CL) phenomenon was found by Albrecht in 1928. In this section, based on the CL reaction of luminol-potassium ferricyanide, luminol-potassium periodate and luminol-dichromate in alkaline medium and combined with flow injection (FI) and controlled-reagent-release technology, fluriode, reserpine and analgin have been determined in water samples, pharmaceutical preparations or body fluids by the proposed method, respectively.(1) A new simple, rapid, selective and sensitive analytical procedure based on the CL detection was described for the determination of free fluoride ion at sub-nanogram level by using controlled-reagent-release technology in FI system. The analytical reagents involved in the CL reaction, including luminol and periodate, were both immobilized on the anion-exchange resins in flow system. Through water injection, luminol and periodate were eluted from the anion exchange column to generate the CL, which was enhanced in the presence of fluoride ion. The increased CL intensity was linear with fluoride ion concentration in the range of 0.1 to 10 ng-ml"1. The limit of detection was 20 pgml"1 (3a) and the relative standard deviation was 1.02% (n = 5) for a 1.0 ng-ml"1 fluoride sample. At a flow rate of 2.0 ml-min"1, including sampling and washing, the detection could be performed in 0.5 min with a relative standard deviation of less than 3.0%. The proposed method had been successfully applied to the determining of free fluoride ion in water and human urine, and the results were in well agreement with results obtained by ion chromatography.(2) A sensitive and rapid FI-CL method with controlled-reagent-release technology for the determination of reserpine was proposed. The CL reagents, luminol and dichromate, used in this sensor, were both immobilized on anion-exchange resin. Through injection of 100 uL of water, the reagents on the anion-exchange resin column were eluted and in the presence of reserpine, the CL intensity was decreased, by which reserpine could be sensed. Reserpine was quantified by measuring the decrement of CL intensity, which was observed linear with the logarithm of reserpine concentration in the range of 1.0 ~ 500.0 ng-ml' , and the limit of detection was 0.4 ng-ml"1 (3a) with a relative standard deviation of less than 3.0%. The proposed procedure was applied in the assay of reserpine in pharmaceutical preparation and biological fluids without any pre-treatment process and with sampling frequencies of 72times per hour.(3) The three methods described the determination of analgin based on its inhibition on the CL of luminol-K3Fe(CN)6, luminol-ICV, luminol-Cr2O72" system. While analgin mixed with these oxidants, by the fast oxidation reaction between analgin and K3Fe(CN)6, IO4" or Cr2O72', oxidant was consumed, which then inhibited the CL reaction of oxidant and luminol in alkaline aqueous solution. The CL emission was correlated with the analgin concentration in the range of 0.1 ~ 100 ng-ml"1, 0.1 ~ 50.0 ng-ml"1, 0.05 ~ 50.0 ng-ml'1, and the detection limit was 0.03, 0.04, 0.02 ng-ml"1 (3ct), respectively. The three methods have been applied successfully to the determination of analgin in pharmaceutical samples and monitoring excretion of analgin in human urine and the mechanism of these homologous CL rections were proposed.
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