Enabling the Triplet of Tetraphenylethene to Sensitize the Excited State of Europium(III) for Protein Detection and Time‐Resolved Luminescence Imaging

• Published in: Advanced science Vol. 3; no. 12; pp. 1600146 - n/a
• Main Authors: Zhu, Zece, Song, Bo, Yuan, Jingli, Yang, Chuluo
• Format: Journal Article
• Language: English
• Published: Germany John Wiley & Sons, Inc 01.12.2016; John Wiley and Sons Inc
• Subjects: Design; Energy; europium complex; Ligands; luminescence probe; protein detection; time‐resolved imaging; China; europium complex; time‐resolved imaging; protein detection; luminescence probe
• ISSN: 2198-3844; 2198-3844
• DOI: 10.1002/advs.201600146

A tetraphenylethene (TPE) group that exhibits aggregation‐induced emission is incorporated into the ligand of a Eu(III) complex (TPEEu) to sensitize the excited state of Eu(III). In steady‐state measurements, TPEEu exhibits weak luminescence when dissolved in aqueous solutions even at a high concentration level, but emits strong fluorescence of TPE and phosphorescence of Eu(III) upon binding with bovine serum albumin. With a delay time of 0.05 ms and a gate time of 1.0 ms in time‐resolved measurements, only phosphorescent emission of Eu(III) is observed with a high on/off ratio. Moreover, this probe is successfully used in time‐resolved luminescence imaging to eliminate the background signal from biological autofluorescence without a washing process. This work provides a general strategy in designing Ln(III) complexes for detecting a broad range of biological molecules. A tetraphenylethene is incorporated into the ligand of a Eu(III) complex (TPEEu) to sensitize the excited state of Eu(III). This probe exhibits a high on/off ratio in detecting bovine serum albumin and is successfully used in time‐resolved luminescence imaging of C. elegans to eliminate the background signal of biological autofluorescence without a washing process.