Key Laboratory of Bioactive Substances and Function of Natural Medicine, Beijing Key Laboratory of Active Substances Discovery and Drugability Evaluation, Institute of Materia Medica, Peking Union Medical College and Chinese Academy of Medical Sciences, 1 Xian Nong Tan Street, 100050, Beijing, China.
ChemistryOpen. 2021 Oct;10(10):1013-1019. doi: 10.1002/open.202100104.
A smart fluorescence "turn-on" probe which contained a dansyl amide fluorophore and an N-oxide group was designed based on the bioorthogonal decaging reaction between N-oxide and the boron reagent. The reaction proceeds in a rapid kinetics (k =57.1±2.5 m s ), and the resulting reduction product showcases prominent fluorescence enhancement (up to 72-fold). Time dependent density functional theoretical (TD-DFT) calculation revealed that the process of photoinduced electron transfer (PET) from the N-oxide moiety to the dansyl amide fluorophore accounts for the quenching mechanism of N-oxide. This probe also showed high selectivity over various nucleophilic amino acids and good biocompatibility in physiological conditions. The successful application of the probe in HaloTag protein labeling and HepG2 live-cell imaging proves it a valuable tool for visualization of biomolecules.
一种基于 N-氧化物与硼试剂之间的生物正交去笼反应的智能荧光“开启”探针，包含丹磺酰基酰胺荧光团和 N-氧化物基团。该反应具有快速动力学（k =57.1±2.5 m s ），并且所得还原产物表现出显著的荧光增强（高达 72 倍）。时变密度泛函理论（TD-DFT）计算表明，N-氧化物部分到丹磺酰基酰胺荧光团的光诱导电子转移（PET）过程解释了 N-氧化物的猝灭机制。该探针还对各种亲核氨基酸具有高选择性，在生理条件下具有良好的生物相容性。该探针在 HaloTag 蛋白标记和 HepG2 活细胞成像中的成功应用证明了它是生物分子可视化的有用工具。
