【作者】 王晓军； 韦小玲； 王立升； 林翠梧；

【Author】 WANG Xiao-jun,WEI Xiao-ling *,WANG Li-sheng,LIN Cui-wu College of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004

【机构】 广西大学化学化工学院；

【摘要】 研究发现,在pH=5-6酸度条件下,当茜素红和吖啶橙混合时,茜素红能使吖啶橙荧光少量猝灭,加入适量的苦参碱,由于其分子的N上含有孤对电子,可与电子接受体茜素红发生荷移反应,形成一种络合物,该络合物最大吸收波长与吖啶橙最大发射波长吻合,络合物和吖啶橙之间能够跟发生有效能量转移使吖啶橙的荧光强度减弱更明显,荧光信号的减弱程度与苦参碱的加入量成良好的线性关系。据此建立了吖啶橙-茜素红体系荧光猝灭法测定苦参碱含量的新方法。实验结果表明该方法在优化条件下,线性范围为14.9-43.5mg.L-1,检出限为1.38mg.L-1,方法精密度为1.24%。该方法用于市售苦参碱杀虫剂及苦参碱栓含量的测定,其回收率在96.6-103%之间,本方法成本低、简单、快速、准确性高。本文通过紫外可见光谱法对方法机理做了深入探讨。更多还原

【Abstract】 It was found that less energy transfer could occur between the acridine orange and alizarin red under the conditions of pH=5-6.Adding an appropriate amount of matrine,it reacted with AR to form charge transfer complex,with matrine as an electron donor because of the it containing lone-pair electrons on N atom and the alizarin red as an electron acceptor.Since the maximum absorption wavelength of the complex in which the ratio of the donor and the acceptor is 2:1 and maximum emission wavelength of acridine orange is about the same,the effective energy transfer could occur between the acridine orange and the complex which resulted in more significant fluorescence quenching of the system.Fluorescence quenching degree of the system and added amount of matrine showed a good linear relationship.Accordingly,a novel fluorescence quenching method for the determination of matrine was established.In the present paper,300 and 527 nm were chosen as the excitation and emission wavelength for measurement of the fluorescence intensity difference ΔF=F 0-F 1 of blank solution and test so lution,and according to positive correlation between the value of ΔF and matrine concentration of test solution.Under the optimum conditions,the linear regression equation was ΔF=12.28ρ+5.50,correlation coefficient was 0.9980,linear range was 14.9～43.5 mg.L-1 and the detection limit was 1.38 mg.L-1,RSD was 1.24%.The method was used to determine the matrine in commercial matrine insecticide and matrine suppositories with satisfactory results.The recoveries were between 96.6% and 103%.With low cost,the method is simple,rapid,and the accuracy is high.In this paper,the method mechanism was further explored by UV spectroscopy.更多还原