State Key Laboratory of Fine Chemicals, School of Chemistry , Dalian University of Technology , Dalian 116024 , China.
Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology , Dalian University of Technology , Linggong Road 2 , Dalian 116024 , China.
Anal Chem. 2019 Feb 19;91(4):2939-2946. doi: 10.1021/acs.analchem.8b05127. Epub 2019 Feb 6.
As a critical gasotransmitter, carbon monoxide (CO) has been demonstrated to be related with mitochondrial respiration, but the monitoring of CO in mitochondria remains a great challenge. In this work, a unique ratiometric time-gated luminescence (TGL) probe, Mito-NBTTA-Tb/Eu, that can specifically respond to mitochondrial CO has been developed. The probe was designed by incorporating a mitochondria-targeting moiety, triphenylphosphonium, into a CO-activatable terpyridine polyacid derivative, 4'-(4-nitrobenzyloxy-2,2':6',2''-terpyridine-6,6''-diyl) bis(methylenenitrilo) tetrakis(acetic acid), for coordinating to Eu and Tb ions to construct lanthanide complex-based probe for ratiometric TGL detection of CO. Upon reaction with CO, accompanied by the conversion of nitro group to amino group, a 1,6-rearrangement-elimination reaction occurs, which leads to the cleavage of 4-nitrobenzyl group from Mito-NBTTA-Tb/Eu, resulting in the significant increase of Tb emission at 540 nm and moderate decrease of Eu emission at 610 nm. After the reaction, the I/ I ratio was found to be 48-fold enhanced. This feature allowed Mito-NBTTA-Tb/Eu to be employed as a ratiometric TGL probe for CO detection with the I/ I ratio as a signal. In addition, the probe showed outstanding mitochondria-localization characteristic, which enabled the probe to be successfully applied to imaging CO within mitochondria of living cells under TGL and ratiometric modes. The application of Mito-NBTTA-Tb/Eu was demonstrated by the visualization and quantitative detection of exogenous and endogenous CO in living cells and mouse liver tissue slices, as well as in living Daphnia magna and mice. All of the results suggested the potential of Mito-NBTTA-Tb/Eu for the quantitative monitoring of CO in vitro and in vivo.
作为一种重要的气体信号分子，一氧化碳（CO）与线粒体呼吸密切相关，但对线粒体中 CO 的监测仍然是一个巨大的挑战。在这项工作中，我们开发了一种独特的比率时间门控发光（TGL）探针 Mito-NBTTA-Tb/Eu，它可以特异性地响应线粒体中的 CO。该探针通过将线粒体靶向部分三苯基膦整合到 CO 激活的三联吡啶多酸衍生物 4'-(4-硝基苄氧基-2,2':6',2''-三联吡啶-6,6''-二基)双(亚甲基亚硝酰基)四乙酸四(乙酸)中，用于与 Eu 和 Tb 离子配位，构建基于镧系元素配合物的探针，用于 CO 的比率 TGL 检测。与 CO 反应后，硝基基团转化为氨基基团，发生 1,6-重排消除反应，导致 Mito-NBTTA-Tb/Eu 中的 4-硝基苄基从探针中裂解，导致 Tb 发射显著增加（在 540nm 处），Eu 发射适度降低（在 610nm 处）。反应后，I/ I 比增强了 48 倍。这一特性使 Mito-NBTTA-Tb/Eu 能够作为 CO 检测的比率 TGL 探针，以 I/ I 比作为信号。此外，该探针表现出出色的线粒体定位特性，使其能够成功地应用于活细胞中线粒体中 CO 的 TGL 和比率模式成像。通过可视化和定量检测活细胞和小鼠肝组织切片中外源性和内源性 CO，以及在活的水蚤和小鼠中，证明了 Mito-NBTTA-Tb/Eu 的应用。所有结果均表明，Mito-NBTTA-Tb/Eu 具有在体外和体内定量监测 CO 的潜力。
