| Chemiluminescence analysis is a trace analysis method Which determines the content of substance according to the light emission of the chemical reaction.There are many merits on CL such as simple and cheap optical system,requiring no light source which avoids the effects of stray light and the instability of light source,and thus providing low background with excellent sensitivity, wide linear range,rapidity,simplicity and so on.Flow-injection chemiluminescence(FI-CL),which combines chemiluminescence(CL) and flow-injection,has high efficiency and accuracy.It becomes more and more important in pharmaceutical analysis.This paper reports the researches of FIA-CL method in pharmaceutical analysis,and the main contents are shown as follows:Chapter 1:SummarizationThe mechanism and principles of CL analysis as well as its history and several common CL analytical systems are mentioned.Some other techniques that are combined with CL analysis have been summarized.The researches and applications of CL in pharmaceutical analysis in recent years have been introduced.The purpose and significance of this study has been pointed out.Chapter 2:Determination of caffeic acid by KMnO4-Rh6G-caffeic acid FIA-CL analysis systemA novel flow-injection chemiluminescence method for the determination of caffeic acid has been proposed based on the strongly enhancing effect of caffeic acid on the chemiluminescence reaction between KMnO4 and Rhodamine 6G in the acid medium.The optimization of the parameters which affected the chemiluminescence signals has been studied.Under the optimum conditions,the method allowed the determination of caffeic acid in the concentration range of 1.0×10-6-1.0×10-4 mol/L,the linear regression equation isâ–³I=-6.16+3.77×106 C and the detection limit(3σ) was 2.4×10-8 mol/L.The relative standard deviation was 3.0%for 11 replicate analyses of 4.0×10-6 mol/L caffeic acid.It has been applied to the determination of caffeic acid in the caffeic acid tablets. Chapter 3:Determination of protocatechuic aldehyde by Ce(â…£)-RhB-protocatechuic aldehyde FIA-CL analysisIn sulphuric acid medium,Ce(â…£) can oxidize protocatechuic aldehyde to produce weak chemiluminescence signal.However,the existence of Rhodamine B can greatly enhance this chemiluminescence signal and the enhanced chemiluminescent intensity was proportional to the concentration of protocatechuic aldehyde in the range of 2.0×10-5-4.0×10-4 mol/L,and the linear regression equation isâ–³Iï¼1.72+1.49×106 C.Based on this phenomenon,a new FIA-CL method for the determination of protocatechuic aldehyde has been established.The detection limit is 3.77×10-8 mol/L and the relative standard deviation is 1.87%for 4.0×10-8 mol/L of protocatechuic aldehyde(n=11).The proposed method was successfully applied to the determination of protocatechuic aldehyde in salvia miltiorrhiza injection.Chapter 4:Determination of quercetin by KMnO4-Rh6G-quercetin FIA-CL analysis systemA simple,sensitive and rapid flow-injection chemiluminescence method had been developed for the determination of quercetin based on the strongly enhancing effect of quercetin on the chemiluminescence reaction between KMnO4 and Rhodamine 6G in an acid medium.The optimization of the parameters which affected the chemiluminescence signals has been studied and the reaction mechanism has been discussed.Under the optimum conditions,the relative chemiluminescence intensity was positively proportional to the concentration of quercetin in the range of 5.0×10-8-7.0×10-5 mol/L and the linear regression equation isâ–³I=-2.22+8.51×106C with the detection limit(3σ) of 3.77×10-9 mol/L.The relative standard deviation was 1.07%for 11 replicate analyses of 1.0×10-6 mol/L quercetin.This method has been successfully applied to the determination of quercetin in the Fufang Yuxingcao Tablets.Chapter 5:Determination of caffeic acid by luminol-K3Fe(CN)6-caffeic acid FIA-CL analysis systemBased on the phenomenon that in an alkaline solution,the CL intensity of the reaction between potassium hexacyanoferrate(â…¢) and luminol could be strongly inhibited by caffeic acid,a new FIA-CL analytical method for the determination of caffeic acid was proposed.The influence of some factors on the chemiluminescence signals has been studied.Under the optimum conditions,the relative chemiluminescence intensity of the system was linear with the concentration of caffeic acid in the range from 3.0×10-8 to 1.0×10-7mol/L and the linear regression equation isâ–³I= 1974.45+ 2.31×1010C;the detection limit(3σ) for caffeic acid was 2.5×10-12 mol/L.The relative standard deviation was 1.93%for 11 replicate analyses of 4.0×10-8 mol/L caffeic acid.The proposed method was applied to the determination of caffeic acid in caffeic acid tables with satisfactory results. Moreover,the reaction mechanism of the chemiluminescence system has been primarily discussed.
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