卤代荧光素荧光猝灭法测定肾上腺色腙

在pH=6.6 的缓冲介质中, 肾上腺色腙(CBZC)与二氯荧光素(DCF)、二溴荧光素(DBF) 和二碘荧光素(DIF)通过静电引力、芳基堆积作用和范德华力形成摩尔比为2: 1的复合物, 引起上述二卤代荧光素的荧光发生猝灭, 最大猝灭波长分别位于533, 536和560 nm. 其荧光猝灭值(ΔF)在一定范围内与肾上腺色腙浓度成正比, 荧光猝灭反应具有较高的灵敏度, 对CBZC的检出限分别为3.3 ng/mL(CBZC-DCF体系), 5.7 ng/mL(CBZC-DBF体系)和129.6 ng/mL(CBZC-DIF体系). 考察了共存物质的影响、荧光猝灭反应的适宜条件和影响因素, 结果表明, 该方法具有良好的选择性, 可用于CBZC的血药和尿药浓度的快速检测. 从温度的影响、荧光寿命以及Stern-Volmer图判断该反应为静态猝灭反应.

Fluorescence Quenching Method for the Determination of Carbazochromum with Halide Fluorescein Dyes

In pH=6.6 Britton-Robinson(BR) buffer medium,a 1∶ 2(molar ratio) compound of dichlorofluorescein(DCF),dibromofluorescein(DBF) or diiodofluorescein(DIF) with carbazochromum(CBZC) was formed by electrostatic attraction,aromatic stacking interaction and van der Waals’ force,which led to fluorescence quenching of above halide fluorescein dyes,and the maximum quenching wavelength were located at 533 nm(DCF),536 nm(DBF) and 560 nm(DIF),respectively.Fluorescence quenching value(ΔF) is proportional to the concentration of CBZC in a certain range.Fluorescence quenching method for the determination of CBZC has high sensitivity,detection limits are 3.3 ng/mL(CBZC-DCF system),5.7 ng/mL(CBZC-DBF system) and 129.6 ng/mL(CBZC-DIF system),respectively.The effect of coexisting substances,the optimum conditions of the reaction and influencing factors were investigated.The results show this method has good selectivity.This method was successfully applied to the quick determination of CBZC in serum and urine samples.Judging from the effect of temperature,fluorescence lifetime determination and the Stern-Volmer plots,the quenching of fluorescence is a static quenching process.