Inner Mongolia Key Laboratory of Chemistry and Physics of Rare Earth Materials, School of Chemistry and Chemical Engineering, Inner Mongolia University, Hohhot 010021, P. R. China.
Inorg Chem. 2020 May 4;59(9):6390-6397. doi: 10.1021/acs.inorgchem.0c00485. Epub 2020 Apr 20.
Due to the disruption by other nonanalyte factors, single-emission probes have been limited in complicated detecting systems. In this work, a pH-modulated luminescence chameleon system based on lanthanide-based MOF (Eu@Mn-MOF), with stable structure and miraculous dual-emitting fluorescent properties, was synthesized by a postsynthetic modification (PSM) strategy of a simple hydrothermal and agitation method. Amazingly, not only can the Eu@Mn-MOF emit a broad emission at 500 nm attributed to the ligand-based fluorescence emission but it can also exhibit the characteristic emission of Eu ions responding to the antenna effect. Moreover, the Eu@Mn-MOF displays an interesting luminescence color transition between acidic and basic solutions. Inspired by this phenomenon, a pH-modulated luminescence chameleon system was first constructed and employed to detect histidine, a kind of basic amino acid for a variety of biological matters, causing a unique fluorescence signal of the ratio-dependent color to change from yellow to light pink which differs from the color change of other water-soluble amino acids. Therefore, Eu@Mn-MOF can be as a practical pH-modulated luminescence chameleon system chemsensor for sensing histidine with low detection limit, high sensitivity, and rapid sensing time. In conclusion, the postsynthetic modified Eu@Mn-MOF has outstanding applications in the fields of chemical detection and human health.
由于其他非分析物因素的干扰，单发射探针在复杂的检测系统中的应用受到了限制。在这项工作中，通过简单的水热和搅拌方法的后合成修饰（PSM）策略，合成了一种基于镧系金属有机骨架（Eu@Mn-MOF）的 pH 调节发光变色龙系统，该系统具有稳定的结构和神奇的双发射荧光特性。令人惊讶的是，Eu@Mn-MOF 不仅可以发射源于配体荧光发射的宽带发射，而且还可以表现出对天线效应的 Eu 离子特征发射。此外，Eu@Mn-MOF 在酸性和碱性溶液之间显示出有趣的发光颜色转变。受此现象启发，首次构建了 pH 调节发光变色龙系统，并用于检测组氨酸，这是一种用于各种生物物质的碱性氨基酸，导致比依赖于荧光信号的独特荧光颜色从黄色变为浅粉色，与其他水溶性氨基酸的颜色变化不同。因此，Eu@Mn-MOF 可以作为一种实用的 pH 调节发光变色龙系统化学传感器，用于检测组氨酸，具有低检测限、高灵敏度和快速传感时间。总之，后合成修饰的 Eu@Mn-MOF 在化学检测和人类健康领域具有突出的应用。
