School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, PR China.
School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2022 Oct 15;279:121490. doi: 10.1016/j.saa.2022.121490. Epub 2022 Jun 7.
Hypochlorous acid/hypochlorite (HOCl/ClO) plays important roles in killing bacterial and causing damage to living tissues, and its abnormal levels could lead to many diseases. Although great efforts have been devoted, fluorescent probes for HOCl/ClO with near-infrared fluorescence, good selectivity/sensitivity, and low background are still important and urgent. In this work, a novel double-bond-linked TCF-aza-BODIPY-based near-infrared fluorescent probe (3) was rationally designed, successfully prepared, and applied for sensing HOCl/ClO in both solutions and living RAW264.7 cells, showing good selectivity and fluorescence "turn-on" phenomenon at 670 nm with low background. The limit of detection towards ClO was determined to be 0.36 μM through the linear fluorescence changes at 670 nm in a broad ClO-concentration range of 0-150 μM. Furthermore, the sensing mechanism was investigated by mass spectrometry and compared with 1, suggesting that the remarkable spectroscopic changes could be ascribed to the oxidization of the double bond to the aldehyde group, accompanied with the leaving of the TCF group. Confocal imaging experiments also confirmed the remarkable intracellular fluorescence enhancements through incubation of ClO and phorbol ester 12-myristate 13-acetate (PMA) in RAW264.7 cells. Therefore, for the first time, we reported a near-infrared TCF-aza-BODIPY-based fluorescent probe for highly sensitive and fluorescence "turn-on" detection of both exogenous and endogenous HOCl in living RAW264.7 cells through the quick oxidation of a conjugated double bond.
次氯酸/次氯酸盐（HOCl/ClO）在杀菌和损伤活组织方面发挥着重要作用，其异常水平可能导致多种疾病。尽管已经付出了巨大的努力，但具有近红外荧光、良好选择性/灵敏度和低背景的 HOCl/ClO 荧光探针仍然是重要且迫切需要的。在这项工作中，我们合理设计、成功制备了一种新型双键连接的 TCF-aza-BODIPY 基近红外荧光探针（3），并将其应用于溶液和活 RAW264.7 细胞中 HOCl/ClO 的检测，在 670nm 处表现出良好的选择性和荧光“开启”现象，背景低。通过在 0-150μM 的宽 ClO-浓度范围内在 670nm 处的线性荧光变化，确定了对 ClO 的检测限为 0.36μM。此外，通过质谱研究并与 1 进行比较，探讨了传感机制，表明显著的光谱变化可归因于双键氧化为醛基，同时伴随 TCF 基团的离去。共聚焦成像实验也证实了 ClO 和佛波酯 12-肉豆蔻酸 13-醋酸盐（PMA）在 RAW264.7 细胞孵育后细胞内荧光的显著增强。因此，我们首次报道了一种近红外 TCF-aza-BODIPY 基荧光探针，可通过共轭双键的快速氧化，对活 RAW264.7 细胞中外源和内源性 HOCl 进行高灵敏度和荧光“开启”检测。
