一种吲哚二甲川菁染料的合成、光谱性质及其应用

The synthesis and spectral properties of a dimethine cyanine dye with indole nucleus and its application

目的合成一种含吲哚环的二甲川菁染料,研究光谱性质、与生物分子的相互作用及其作为荧光探针在活细胞成像中的应用。方法采用UV-vis,1H NMR,IR,HR-MS分析确证产物的结构;采用吸收光谱和荧光光谱法研究二甲川菁染料在不同溶剂中的光谱性质,以及该染料在生理条件下与鲑鱼精DNA(DNA)、牛血清白蛋白(BSA)、溶菌酶、淀粉酶、糜蛋白酶和牛血红蛋白的相互作用;采用荧光倒置显微镜观察染料对K562白血病细胞的活细胞染色。结果该染料最大吸收波长(λmax)随着溶剂介电常数的增加出现蓝移。染料与DNA相互作用较强,且荧光强度随着DNA浓度的增加而增强,而其他5种生物大分子对染料的荧光强度影响不大。该染料可以穿透活细胞膜,对细胞核染色,可以清晰地看出核仁的荧光较亮,2 h后观察细胞仍有荧光。结论合成了一种光谱性质优良的二甲川菁染料,该染料对核酸(DNA/RNA)有较强的亲和性,属于活细胞通透性染料,是一种潜在的活细胞成像荧光探针。

Aim To synthesize a dimethine cyanine dye with indole nucleus and study its spectral properties and interaction with biomolecules as well as its application in living cell imaging. Methods The structure of the pre- pared dye was confirmed by 1H NMR, IR, UV-vis and HR-MS. Spectral properties of the prepared dye in different solvents and the interactions between the dye and Salmon Sperm DNA （DNA）, Bovine Serum Albumin （BSA）, Muramidase, Amylase, Bovine Hemoglobin and Chymotrypsin, respectively, were investigated by absorption and fluorescence spectra. Living cell imaging of K562 leukemic cells was assayed by fluorescence convert microscope. Results The/~ max of the dye was blue-shifted with the increase of the solvent dielectric constant. It was found that the interaction of the dye with DNA was strong, and fluorescence intensities of the dye were increased with the in- crease of DNA＇s concentrations, while the increase became slight when it interacted with the other five biomole- cules. The dye was cell-permeant, dyed the cell nuclear. It was clear to see that the nucleolar part showed clear fluorescence which could still be observed 2 hours later. Conclusion The prepared dye showed excellent fluorescence and good affinity for DNA/RNA. It belongs to a cell-permeant dye which has potential to be applied as fluo- rescence probe in living cell imaging.