Ding Zhaoyang, Wang Chunfei, Feng Gang, Zhang Xuanjun
Faculty of Health Sciences, University of Macau, Taipa, Macau SAR, China.
ACS Omega. 2018 Aug 17;3(8):9400-9406. doi: 10.1021/acsomega.8b01489. eCollection 2018 Aug 31.
An energy-transfer metal-organic nanoprobe is designed for ratiometric sensing with dual response to both peroxynitrite (ONOO) and hypochlorite (ClO). Here, a nanoscale metal-organic framework (NMOF) acts as the energy donor and molecular probe as the acceptor to construct a Förster resonance energy transfer (FRET) nanosystem. Biocompatible dextran conveniently binds to the NMOF surface through multiple weak coordination interactions to improve water dispersibility and cell uptake. Dextran can also coordinate with the molecular probe with arylboronic acid group, which enables the convenient grafting of molecular probes to the NMOF surface to construct energy-transfer nanoprobes. Because of efficient FRET, the bright blue fluorescence of NMOF is quenched, whereas red emission from the acceptor is enhanced. Upon reacting with ONOO, the probe departs from NMOF and the fluorescence of NMOF is recovered because of the interruption of FRET. When reacting with ClO, the phenothiazine moiety in the molecular probe is oxidized into phenothiazine-5-oxide, which leads to more efficient energy transfer and the fluorescence shifts from red to orange. The nanoprobes are also successfully applied to the detection of ONOO and ClO in living cells.
设计了一种能量转移金属有机纳米探针，用于对过氧亚硝酸盐（ONOO）和次氯酸盐（ClO）具有双重响应的比率传感。在此，纳米级金属有机框架（NMOF）作为能量供体，分子探针作为受体，构建了福斯特共振能量转移（FRET）纳米系统。生物相容性葡聚糖通过多个弱配位相互作用方便地结合到NMOF表面，以改善水分散性和细胞摄取。葡聚糖还可以与带有芳基硼酸基团的分子探针配位，这使得分子探针能够方便地接枝到NMOF表面以构建能量转移纳米探针。由于高效的FRET，NMOF的亮蓝色荧光被淬灭，而受体的红色发射增强。与ONOO反应时，探针从NMOF上脱离，由于FRET的中断，NMOF的荧光得以恢复。与ClO反应时，分子探针中的吩噻嗪部分被氧化为吩噻嗪-5-氧化物，这导致更有效的能量转移，荧光从红色变为橙色。该纳米探针也成功应用于活细胞中ONOO和ClO的检测。
