聚电解质诱导的硫代黄素 T 激基缔合物及其对温度的荧光比率传感

摘要

In the present paper, the authors studied the effects of anionic polyelectrolyte sodium polystyrene sulfonate (PSS) on the cationic dye thioflavin T (ThT) fluorescence spectra in aqueous solution. The influencing factors of the formed thioflavin T excimer in the existence of PSS were investigated. Experimental results show that PSS could increases the local eoncentration of ThT by electrostatic attraction, therefore enhances excimer formation of thioflavin T. The fluorescenCe intensity of ThT monomer and excimer (IM and IE) changes regularly along with the change in temperature; ln(IE/IM) and 1/T have good linear relationship. Hereby we have developed a new type of fluorescence ratiometric sensor for temperature which could be recognized by naked eye, and it could effectively eliminate environmental effects such as instability of exciting light intensity and photobleaching, therefore improve the accuracy of identification.%研究了在水溶液中阴离子聚电解质聚苯乙烯磺酸钠(PSS)对阳离子型染料硫代黄素 T(ThT)荧光光谱的影响,并考察了 PSS 存在下,ThT 在水溶液中所形成激基缔合物的影响因素.实验证明,通过静电吸引作用,PSS 可以增加 ThT 的局部浓度,从而显著地促进 ThT 激基缔合物的形成;ThT 单体及其激基缔合物荧光强度(IM及IE)随温度的变化发生有规律的变化,In(IM及IE)与I/T有较好的线性关系,据此可建立一种新型的对温度敏感的可裸眼识别的荧光比率传感,该传感可有效地消除激发光强度的不稳定性和光强漂移等环境因素的影响,提高了识别的准确度.