Carbazole tricationic salt:A novel potential two-photon fluorescent DNA probe for nucleic imaging of cells  

作　　者：ZHAO Ning ZHANG YuanHong LIU Xin YU XiaoQiang GE MaoFa 

机构地区：[1]State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China [2]Beijing National Laboratory for Molecular Sciences (BNLM), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China

出　　处：《Chinese Science Bulletin》2010年第32期3661-3667,共7页

基　　金：supported by the National Natural Science Foundation of China (50673053, 50173015, 30771091 and 50721002);National Science Foundation of China/the Hong Kong Research Grants Council (50218001)

摘　　要：A new carbazole tricationic salt,4,4'-(1E,1'E)-2,2'-(9-(2-(1-(2-hydroxyethyl)pyridinium-4-yl)ethyl)-9H-carbazole-3,6-diyl) bis(ethane-2,1-diyl) bis(1-(2-hydroxyethyl)pyridinium) iodide (THEPC) was synthesized. Photophysical experiments have shown that THEPC has large two-photon excited fluorescence action cross-sections (33 GM in the presence of DNA),which ranks THEPC as a good biological fluorophore. The results from electronic absorption,circle dichroism and single-/two-photon fluorescence emission spectra suggest that THEPC can strongly bind to DNA,with an intrinsic binding constant of 5.79 × 106 L mol-1. THEPC has better photostability under one-or two-photon excitation conditions. Finally,the staining photos from two-photon fluorescence microscopy (TPM) show that THEPC can exclusively label the nucleus with high contrast and without image distortion. These remarkable properties and optimized imaging ability make THEPC an attractive DNA probe in TPM.A new carbazole tricationic salt, 4,4＇-（1E,1＇E）-2,2＇-（9-（2-（1-（2-hydroxyethyl）pyridinium-4-yl）ethyl）-9H-carbazole-3,6-diyl） bis（ethane- 2,1-diyl） bis（1-（2-hydroxyethyl）pyridinium） iodide （THEPC） was synthesized. Photophysical experiments have shown that THEPC has large two-photon excited fluorescence action cross-sections （33 GM in the presence of DNA）, which ranks THEPC as a good biological fluorophore. The results from electronic absorption, circle dichroism and single-/two-photon fluorescence emission spectra suggest that THEPC can strongly bind to DNA, with an intrinsic binding constant of 5.79 x 106 L mo1-1. THEPC has better photostability under one- or two-photon excitation conditions. Finally, the staining photos from two-photon fluorescence microscopy （TPM） show that THEPC can exclusively label the nucleus with high contrast and without image distortion. These remarkable properties and optimized imaging ability make THEPC an attractive DNA probe in TPM.

关 键 词：双光子激发荧光 DNA探针 荧光成像 咔唑 核酸 细胞 荧光发射光谱 盐 

分 类 号：O561.2[理学—原子与分子物理] Q523[理学—物理]