Yuan Youyong, Zhang Ruoyu, Cheng Xiamin, Xu Shidang, Liu Bin
Department of Chemical and Biomolecular Engineering , National University of Singapore , 4 Engineering Drive 4 , Singapore 117585 . Email:
Institute of Materials Research and Engineering , Agency for Science , Technology and Research (ASTAR) , 3 Research Link , 117602 , Singapore.
Chem Sci. 2016 Jul 1;7(7):4245-4250. doi: 10.1039/c6sc00055j. Epub 2016 Mar 16.
The accurate detection of biological substances is highly desirable to study various biological processes and evaluate disease progression. Herein, we report a self-validated fluorescent probe which is composed of a coumarin fluorophore as the energy donor and a fluorogen with aggregation-induced emission characteristics (AIEgen) as the energy quencher linked through a caspase-3 specific peptide substrate. Unlike the traditionally widely studied fluorescence resonance energy transfer (FRET) probes, our new generation of FRET probe is non-fluorescent itself due to the energy transfer as well as the dissipation of the acceptor energy through the free molecular motion of AIEgen. Upon interaction with caspase-3, the probe displays strong green and red fluorescent signals synchronously due to the separation of the donor-quencher and aggregation of the released AIEgen. The fluorescence turn-on with dual signal amplification allows real-time and self-validated enzyme detection with a high signal-to-background ratio, providing a good opportunity to accurately monitor various biological processes in a real-time manner.
准确检测生物物质对于研究各种生物过程和评估疾病进展非常重要。在此，我们报告了一种自验证荧光探针，它由香豆素荧光团作为能量供体和具有聚集诱导发光特性（AIEgen）的荧光团作为能量猝灭剂组成，通过半胱天冬酶-3特异性肽底物连接。与传统上广泛研究的荧光共振能量转移（FRET）探针不同，我们新一代的FRET探针本身不发荧光，这是由于能量转移以及通过AIEgen的自由分子运动导致受体能量耗散。与半胱天冬酶-3相互作用时，由于供体-猝灭剂的分离和释放的AIEgen的聚集，探针同时显示出强烈的绿色和红色荧光信号。具有双信号放大的荧光开启允许以高信噪比进行实时和自验证的酶检测，为实时准确监测各种生物过程提供了良好的机会。
