Ketocoumarin dye 3-acetyl-7-diethylaminecoumrin was synthesized and charater ized. The spectra and photophysics behavior were studied in different aprotic solvents. Results showed that the fluorescence quantum yield h...Ketocoumarin dye 3-acetyl-7-diethylaminecoumrin was synthesized and charater ized. The spectra and photophysics behavior were studied in different aprotic solvents. Results showed that the fluorescence quantum yield had a maximum and the ratio of non-radiative transition rate to radiative transition rate had a minimum with the increasing of the solvent polarity. Also, the fluorescence of the dye can be quenched by triethylamine and the change is in accordance with the Stern-Volmer formula. These phenomenon was discussed preliminarily.展开更多
通过Knoevenagel缩合反应合成了探针分子1,探针分子1的结构用1 H NMR进行了表征。通过紫外-可见光谱及荧光光谱研究了探针分子1检测CN^(-)的能力,结果显示,向探针1的二甲基亚砜(DMSO)-H2O(95∶5,V∶V)磷酸缓冲盐溶液体系(PBS,pH=7.4)中...通过Knoevenagel缩合反应合成了探针分子1,探针分子1的结构用1 H NMR进行了表征。通过紫外-可见光谱及荧光光谱研究了探针分子1检测CN^(-)的能力,结果显示,向探针1的二甲基亚砜(DMSO)-H2O(95∶5,V∶V)磷酸缓冲盐溶液体系(PBS,pH=7.4)中加入Na^(+)、Ca^(2+)、Mg^(2+)、F^(-)、Cl^(-)、Br^(-)、I^(-)、AcO^(-)、H_(2)PO_(4)^(-)、NO_(3)^(-)、NO_(2)^(-)和CN^(-)后,仅CN^(-)可使探针1溶液的颜色由蓝色变为黄色,吸收光谱发生明显的变化(不受其他分析物的干扰)。探针1识别CN^(-)非常迅速,能够在较宽的pH范围内进行检测。在荧光滴定光谱中,探针1检测CN^(-)的检出限为0.14μmol/L,低于饮用水中CN^(-)的极限质量浓度(1.9μmol/L),表明探针1可用于环境和食品样品中CN^(-)的定性、定量检测。同时,基于探针1制备了CN^(-)快速检测试纸,该试纸被成功地应用于自来水样品和添加氰化物食品(辣白菜)中的现场快速检测。展开更多
Seven novel fluorescent coumarin derivatives were synthesized from 7-diethylamino-4-chloro-3-formyl-coumarin. The spectra of absorption, excitation and emission were dependent not only on the structures and also on th...Seven novel fluorescent coumarin derivatives were synthesized from 7-diethylamino-4-chloro-3-formyl-coumarin. The spectra of absorption, excitation and emission were dependent not only on the structures and also on the concentration of dyes. The PPP-MO predictions can only be consistent with the spectra in dilute solutions.展开更多
Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 （C307） and acriflavine （ACF） laser dyes in liquid and solid phases have been studied. A cw LD la...Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 （C307） and acriflavine （ACF） laser dyes in liquid and solid phases have been studied. A cw LD laser source of 1 mW and 407 nm wavelength was used as an exciting source. For one hour exposure time, it was found that the solid dye samples suffer photobleaching more than the liquid dye samples. This is because in liquid solutions the dye molecules can circulate during the irradiation, while the photobleaching is a serious problem when the dye is incorporated into solid matrix and cannot circulate.展开更多
文摘Ketocoumarin dye 3-acetyl-7-diethylaminecoumrin was synthesized and charater ized. The spectra and photophysics behavior were studied in different aprotic solvents. Results showed that the fluorescence quantum yield had a maximum and the ratio of non-radiative transition rate to radiative transition rate had a minimum with the increasing of the solvent polarity. Also, the fluorescence of the dye can be quenched by triethylamine and the change is in accordance with the Stern-Volmer formula. These phenomenon was discussed preliminarily.
文摘通过Knoevenagel缩合反应合成了探针分子1,探针分子1的结构用1 H NMR进行了表征。通过紫外-可见光谱及荧光光谱研究了探针分子1检测CN^(-)的能力,结果显示,向探针1的二甲基亚砜(DMSO)-H2O(95∶5,V∶V)磷酸缓冲盐溶液体系(PBS,pH=7.4)中加入Na^(+)、Ca^(2+)、Mg^(2+)、F^(-)、Cl^(-)、Br^(-)、I^(-)、AcO^(-)、H_(2)PO_(4)^(-)、NO_(3)^(-)、NO_(2)^(-)和CN^(-)后,仅CN^(-)可使探针1溶液的颜色由蓝色变为黄色,吸收光谱发生明显的变化(不受其他分析物的干扰)。探针1识别CN^(-)非常迅速,能够在较宽的pH范围内进行检测。在荧光滴定光谱中,探针1检测CN^(-)的检出限为0.14μmol/L,低于饮用水中CN^(-)的极限质量浓度(1.9μmol/L),表明探针1可用于环境和食品样品中CN^(-)的定性、定量检测。同时,基于探针1制备了CN^(-)快速检测试纸,该试纸被成功地应用于自来水样品和添加氰化物食品(辣白菜)中的现场快速检测。
基金Supported by the State Key Laboratory of Dyes and Surfactants Fine Chemicals.
文摘Seven novel fluorescent coumarin derivatives were synthesized from 7-diethylamino-4-chloro-3-formyl-coumarin. The spectra of absorption, excitation and emission were dependent not only on the structures and also on the concentration of dyes. The PPP-MO predictions can only be consistent with the spectra in dilute solutions.
文摘Under high-excitation irradiance conditions to induce fluorescence, the dependence of photobleaching of Coumarin 307 （C307） and acriflavine （ACF） laser dyes in liquid and solid phases have been studied. A cw LD laser source of 1 mW and 407 nm wavelength was used as an exciting source. For one hour exposure time, it was found that the solid dye samples suffer photobleaching more than the liquid dye samples. This is because in liquid solutions the dye molecules can circulate during the irradiation, while the photobleaching is a serious problem when the dye is incorporated into solid matrix and cannot circulate.
