State Key Laboratory of Luminescent Materials and Devices, College of Materials Science and Engineering , South China University of Technology , Guangzhou 510640 , China.
Anal Chem. 2018 Aug 7;90(15):9359-9365. doi: 10.1021/acs.analchem.8b01968. Epub 2018 Jul 25.
Squaraine dyes have excellent photostability with intensive absorption and strong fluorescence in the near-infrared (NIR) region. However, they display a strong tendency to aggregate in aqueous media because of their poor water solubility, often causing fluorescence quenching that severely limits their in vivo applications, especially for detecting or imaging diagnostic enzymes. In this work, an oligo(ethylene glycol)-functionalized squaraine fluorophore has been developed as an NIR-fluorescent probe that can detect and image the activities of a diagnostic enzyme (leucine aminopeptidase) both in vitro and in vivo. The probe shows near-infrared absorption and emission, a low detection limit (0.61 ng/mL), relatively good aqueous solubility, high selectivity, and little toxicity. In addition, the probe herein was successfully used to track endogenous leucine aminopeptidase both in vitro and in vivo with a nude-mouse model.
方酸染料具有优异的光稳定性，在近红外（NIR）区域具有强烈的吸收和强荧光。然而，由于其较差的水溶性，它们在水介质中容易聚集，常常导致荧光猝灭，这严重限制了它们在体内的应用，特别是用于检测或成像诊断酶。在这项工作中，开发了一种聚（乙二醇）功能化的方酸荧光团作为近红外荧光探针，可在体外和体内检测和成像诊断酶（亮氨酸氨基肽酶）的活性。该探针具有近红外吸收和发射、低检测限（0.61ng/mL）、相对良好的水溶性、高选择性和低毒性。此外，该探针还成功地用于追踪裸鼠模型体内和体外的内源性亮氨酸氨基肽酶。
