Department of Biological Science and Technology, Institute of Molecular Medicine and Bioengineering, National Chiao Tung University, 75 Bo-Ai Street, Hsinchu 300, Taiwan.
Inorg Chem. 2012 May 7;51(9):5400-8. doi: 10.1021/ic300379u. Epub 2012 Apr 9.
The stable, water-soluble, and nonfluorescent FA-OMe can sense nitric oxide (NO) and form the intensely fluorescent product dA-FA-OMe via reductive deamination of the aromatic primary amine. The reaction is accompanied by a notable increase of the fluorescent quantum yield from 1.5 to 88.8%. The deamination mechanism of FA-OMe with NO was proposed in this study. The turn-on fluorescence signals were performed by suppression of photoinduced electron transfer (PeT), which was demonstrated by density functional theory (DFT) calculations of the components forming FA-OMe and dA-FA-OMe. Furthermore, FA-OMe showed water solubility and good stability at physiological pHs. Moreover, the selectivity study indicated that FA-OMe had high specificity for NO over other reactive oxygen/nitrogen species. In an endogenously generated NO detection study, increasing the incubation time of FA-OMe with lipopolysaccharide (LPS) pretreated Raw 264.7 murine macrophages could cause an enhanced fluorescence intensity image. In addition, a diffusion/localization cell imaging study showed that FA-OMe could be trapped in Raw 264.7 cells. These cell imaging results demonstrated that FA-OMe could be used as a turn-on fluorescent sensor for the detection of endogenously generated NO.
FA-OMe 稳定、水溶性好且非荧光，可通过芳香伯胺的还原脱氨作用来感应一氧化氮（NO）并生成强荧光产物 dA-FA-OMe。该反应伴随着荧光量子产率从 1.5 显著增加至 88.8%。本研究提出了 FA-OMe 与 NO 的脱氨反应机制。通过光诱导电子转移（PeT）的抑制实现了荧光信号的开启，这通过形成 FA-OMe 和 dA-FA-OMe 的组件的密度泛函理论（DFT）计算得到了证明。此外，FA-OMe 在生理 pH 值下具有水溶性和良好的稳定性。此外，选择性研究表明，FA-OMe 对 NO 具有高度特异性，而对其他活性氧/氮物质的选择性较低。在内源性 NO 检测研究中，增加 FA-OMe 与脂多糖（LPS）预处理的 Raw 264.7 鼠巨噬细胞孵育时间可导致荧光强度图像增强。此外，扩散/定位细胞成像研究表明 FA-OMe 可被捕获在 Raw 264.7 细胞中。这些细胞成像结果表明，FA-OMe 可作为用于检测内源性产生的 NO 的开启型荧光传感器。
