摘要/Abstract

高半胱氨酸（Hcy）被认为是血管和肾脏疾病的危险因素.因此，开发Hcy特异性荧光探针，特别是比率荧光探针具有重要的意义.基于邻羟基醛基化的苯并噻唑，合成了一种用于Hcy高选择性检测的比率荧光探针3-（苯并噻唑-2-基）-2-羟基-5-甲基苯甲醛（BA）.相对于其他测试物种（包括半胱氨酸和谷胱甘肽），该探针BA对Hcy表现性出良好的选择性.探针BA自身显示出绿色荧光（544 nm），将Hcy加入到探针溶液中后，反应体系表现出蓝色荧光（478 nm）.在0~1.0 mmol/L浓度范围内，荧光发射强度比值（I_{478 nm}/I_{544 nm}）与Hcy呈现良好的线性关系，检测限为1.6 mmol/L.该探针BA毒性低，渗透性好，能够用于细胞中的Hcy比率荧光成像，显示其在生物体系中潜在的应用.另外，通过核磁、质谱实验和密度泛函理论计算验证了探针对Hcy的识别机理.
关键词: 高半胱氨酸, 比率, 荧光探针, 细胞成像
Elevated homocysteine (Hcy) has been considered as a risk factor for vascular and renal diseases. Therefore, the development of Hcy-specific fluorescent probes, especially ratiometric fluorescent probes is of great importance. In the present study, a highly Hcy selective ratiometric fluorescent probe 3-(benzo[d]thiazol-2-yl)-2-hydroxy-5-methyl-benzaldehyde (BA), based on an ortho-hydroxy aldehyde functionalized benzothiazole, is presented. The probe responded selectively to Hcy over other tested species including Cys and GSH with ratiometric fluorescence changes. The probe possessed itself green fluorescence (λ_em=544 nm). Addition of Hcy to the BA solution triggered remarkable blue fluorescence (λ_em=478 nm). The fluorescence intensity ratios (I_{478 nm}/I_{544 nm}) were linearly related to the amounts of Hcy from 0 to 1.0 mmol/L with a detection limit of 1.6 μmol/L. The probe BA possessed low cytotoxicity and desirable cell permeability, and could be employed for the ratiometric imaging of Hcy in living cells, suggesting its potential applications in biological systems. Moreover, the sensing mechanism of BA for Hcy was verified by NMR, HRMS and time-dependent density function theory calculations.
Key words: homocysteine, ratiometric, fluorescent probe, cell imaging


PDF全文下载地址:

点我下载PDF