A versatile water soluble fluorescent probe for ratiometric sensing of Hg2+ and bovine serum albumin
作者:Jinghan Wen、Zhirong Geng、Yuxin Yin、Zhilin Wang
DOI:10.1039/c1dt10362h
日期:——
A novel tetraazamacrocycle fluorescent sensor (6-(1-(dimethylamino)-5-naphthalene sulfonyl)-3,6,9,15-tetraazabicyclo[9.3.1] pentadeca-1(15),11,13-triene, 1) has been designed and prepared, which can be utilized for selective and ratiometric sensing of Hg2+ and bovine serum albumin (BSA) with two different responsive modes in aqueous solution at physiological pH (50 mM Tris-HCl, pH 7.6). Above 0.5 ppb Hg2+ can be discerned by coordination with 1 and the emission color changes enable 1 to be applied to a fast Hg2+ test paper assay. Sensor 1 has also been demonstrated to be easily cell-penetrable and applicable for Hg2+ imaging in living cells. Imaging of BSA in the gel using SDS-PAGE (sodium dodecyl sulfate polyacrylamide gel electrophoresis) stained in the medium containing 1 verified that the binding of 1 and BSA was successful in the presence of nonprotein substances. The linear range of 1 towards BSA utilizing ratiometric fluorescent calibration via noncovalent interaction in solution is 0–100 μg mL−1 with a detection limit of 1 μg mL−1, and has been successfully employed to determine the albumin concentration in blood serum by means of ratiometric fluorescent measurements for the first time. Finally, sensor 1 behaves as a fluorescent molecular switch composed of triple logic gates upon chemical inputs of Hg2+ and BSA, which potentially provides intelligent diagnostics for Hg2+ contaminated serum on the nanoscale.
设计并制备了一种新型四氮杂大环荧光传感器(6-(1-(二甲氨基)-5-萘磺酰基)-3,6,9,15-四氮杂二环[9.3.1]十五烷-1(15),11,13-三烯,1),该传感器可在生理pH条件下(50 mM Tris-HCl,pH 7.6)的水溶液中,利用两种不同的响应模式选择性地对Hg2+和牛血清白蛋白(BSA)进行比率型检测。通过与1的配位,可以辨别出高于0.5 ppb的Hg2+,其发射颜色的变化使得1能够应用于快速Hg2+试纸检测。此外,1还表现出良好的细胞通透性,适用于活细胞中Hg2+的成像。使用含有1的介质对BSA进行SDS-PAGE(十二烷基硫酸钠-聚丙烯酰胺凝胶电泳)染色凝胶成像,验证了在非蛋白质物质存在下,1与BSA的结合是成功的。通过非共价相互作用,利用比率荧光校准法,1对BSA的线性范围为0-100 μg mL-1,检测限为1 μg mL-1,并首次成功应用于通过比率荧光测定法测定血清中白蛋白的浓度。最后,1在Hg2+和BSA的化学输入下表现为由三重逻辑门组成的荧光分子开关,这可能为纳米尺度上受到Hg2+污染的血清提供智能诊断。