SENSITIZATION OF SURFACTANT ON THE FLUORESCENT REACTIONS OF METALS
SHI HUI-MING~* CUI WAN-CANG WANG RU-JI(Department of Chemistry, Nankai University, Tianjin)
The effects of different surfactants on Hf-quercetin, Zr-quercetin, Sn-morin, Mg-oxine-5-sulfonic acid (H_2QS), Zn-H_2QS, Cd-H_2QS and Tb-EDTA-sulfosalicylic acid (SSA) systems were investigated. It was found that the fluorescence intensity of each complex studied is increased greatly in the presence of a suitable surfactant. The optimum conditions of formation of the ternary complexes involving a surfactant were found, and the compositions of these ternary complexes were established by fluorometry. In the presence or absence of a surfactant, the quantum efficiencies (φ) of fluorescent complexes were measured by relative method, and their molar absorptivities at the excitation wavelength (ε_(ex)) wore calculated. It was found that the quantum efficiencies and molar absorptivities of fluorescent complexes were increased to various degrees due to the formation of the ionic associated complexes with fixed composition, and their fluorescence intensity was increased greatly thereby. The function of surfactant micellar and the relation between the molecular structures of surfactants and their effects on the fluorescent reactions were discussed. It is noted that only by the surfactants in the molecule of which the aromatic system is not charged or connected directly with a charged functional group can the fluorescent reactions be sensitized. With the sensitization of surfactant it is possible to develop some fluorometries of metals which are highly sensitive.