Peng Lu, Gao Meng, Cai Xiaolei, Zhang Ruoyu, Li Kai, Feng Guangxue, Tong Aijun, Liu Bin
Department of Chemistry, Beijing Key Laboratory for Analytical Methods and Instrumentation, Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical Biology, Tsinghua University, Beijing 100084, P. R. China.
J Mater Chem B. 2015 Dec 21;3(47):9168-9172. doi: 10.1039/c5tb01938a. Epub 2015 Nov 9.
A novel fluorescent probe SA-βGal is reported here with light-up response to β-galactosidase. SA-βGal possesses the β-galactopyranoside group to react with β-galactosidase and releases the fluorescent salicylaldehyde azine with both aggregation induced emission (AIE) and excited-state intramolecular proton transfer (ESIPT) characteristics. The linear fluorescent response enables the in vitro quantification of β-galactosidase activity in a range of 0-0.1 U mL with a detection limit of 0.014 U mL. The probe exhibits significant advantages, such as no self-quenching at high concentrations, a large Stokes shift (190 nm) and high specificity to β-galactosidase with an excellent light-up ratio of 820 fold. Moreover, thanks to its good retention in living cells, the application of SA-βGal for the imaging of cellular β-galactosidase was also achieved with high contrast.
本文报道了一种新型荧光探针SA-βGal，它对β-半乳糖苷酶具有点亮响应。SA-βGal具有β-吡喃半乳糖苷基团，可与β-半乳糖苷酶反应，并释放出具有聚集诱导发光（AIE）和激发态分子内质子转移（ESIPT）特性的荧光水杨醛嗪。线性荧光响应能够在0-0.1 U/mL范围内对β-半乳糖苷酶活性进行体外定量，检测限为0.014 U/mL。该探针具有显著优势，如高浓度下无自猝灭、大斯托克斯位移（190 nm）以及对β-半乳糖苷酶具有高特异性，其出色的点亮倍数为820倍。此外，由于其在活细胞中的良好保留，SA-βGal还成功用于细胞β-半乳糖苷酶的高对比度成像。
