发光标记物--异硫氰酸曙红荧光的介质效应

详细研究了介质 (pH、有机溶剂、表面活性剂 )对异硫氰酸曙红 (Eosin NCS)荧光的影响。结果表明 ,体系的pH和极性是影响Eosin NCS荧光的两个主要因素。Eosin5 NCS在弱酸性介质中的荧光强度明显高于在弱碱性介质中的荧光强度 ,但荧光强度随溶液 pH的变化较敏感 ,需要小心控制。表面活性剂与Eosin5 NCS的作用表现出明显的电性选择性 ,CTMAB对Eosin NCS荧光的影响存在着单分子猝灭和胶束增敏作用两个过程 ;当有CTMAB胶束存在时 ,Eosin NCS在弱碱性介质中荧光强度可达到甚至超过其在弱酸性介质中的荧光强度。在高含量有机溶剂存在时 ,Eosin5 NCS荧光亦可显著增强 ,应充分利用这些特性。

The Medium Effects of Fluorescence of Eosin-5-Isothiocynate as a Luminescent Marker

In this paper, the medium (pH, organic solvent and surfactant) effects on fluorescence of eosin-5-isothiocynate(eosin-ITC) have been studied in detail. The results show that the pH and polarity of system studied are two great important influence factors on fluorescence of eosin-ITC. The fluorescence intensity of eosin-ITC in weak acidic medium is higher obviously than that of in weak basic medium, but it is sensitive to change of pH, be careful to use. The reaction between surfactant and eosin-ITC shows a good electric selectivety, and the effect of CTMAB on fluorescence of eosin-ITC can be classified as two stages: monomer quenching (below cmc) and micelle sensibilization (above cmc). In the presence of micelle of CTMAB, the fluorescence intensity of eosin-ITC in weak basic medium is even higher than that of in weak acidic medium. In the presence of high organic solvent content, the fluorescence intensity of eosin-ITC is also increased obviously. These properties are available for use.