比率型亚硫酸氢根荧光探针的构建及其生物成像研究

A ratiometric fluorescent probe for sensing bisulphate and its application in living cells and zebrafish

本文基于萘并吡喃-吲哚盐共轭体系设计合成了能够检测亚硫酸氢根(HSO_3^-)的新型近红外比率型荧光探针.该探针对HSO_3^-识别显示出优异的选择性、较高的灵敏度和超快速的荧光响应.加入HSO_3^-后,探针展现出21.6倍(I_(520)/I_(653))的相对荧光强度的增强,并伴随着溶液颜色由紫色转变为无色.此外,高分辨率质谱和核磁氢谱滴定共同证实了该探针对HSO_3^-的检测机制是HSO_3^-与探针的不饱和碳碳双键发生了亲核加成反应.最后,探针被成功地应用于活细胞和斑马鱼幼体中HSO_3^-的原位示踪.

A novel near-infrared fluorescent probe for detection of bisulfite was designed and developed based on a conjugated naphthopyran-indolium system. The sensor showed excellent selectivity, high sensitivity and a rapid response toward bisulfite in aqueous solution. Upon the addition of HSO_3^-,the sensor displayed 21.6-fold （I_（520）/I_（653））fluorescence intensity enhancement, accompanied with an apparent color change from violet to colorless, suggesting that the sensor can be used to detect HSO_3^- with ＂naked-eye＂. The lowest detection limit for the above measurement was found to be 76 nM, and it was sensitive enough for the detection of endogenously produced bisulfite in biological system. Furthermore, the sensing mechanism was confirmed by high-resolution mass spectroscopy analysis and 1HNMR spectrometry analysis, which was based on the strong nucleophilic addition reaction of bisulfite towards the sensor. Moreover, as a biocompatible molecule, the probe was successfully used for fluorescence imaging of bisulfite in MCF-7 cells and zebrafish, demonstrating that the probe is a novel ratiometric fluorescent probe to image SO_2 derivatives in biosystem.