Journal Papers

Song, Bo

Yuan, JL (reprint author), Dalian Univ Technol, Sch Chem, State Key Lab Fine Chem, Dalian 116024, Peoples R China.

Ye, Zhiqing,Yang, Yajie,Ma, Hua,Zheng, Xianlin,Jin, Dayong,Yuan, Jingli

2015-09-16

SCIENTIFIC REPORTS

SCIE、PubMed、Scopus

J

5

14194

2045-2322

Sensitive optical imaging of active biomolecules in the living organism requires both a molecular probe specifically responsive to the target and a high-contrast approach to remove the background interference from autofluorescence and light scatterings. Here, a responsive probe for ascorbic acid (vitamin C) has been developed by conjugating two nitroxide radicals with a long-lived luminescent europium complex. The nitroxide radical withholds the probe on its "off" state (barely luminescent), until the presence of vitamin C will switch on the probe by forming its hydroxylamine derivative. The probe showed a linear response to vitamin C concentration with a detection limit of 9.1 nM, two orders of magnitude lower than that achieved using electrochemical methods. Time-gated luminescence microscopy (TGLM) method has further enabled real-time, specific and background-free monitoring of cellular uptake or endogenous production of vitamin C, and mapping of vitamin C in living Daphnia magna. This work suggests a rational design of lanthanide complexes for backgroundf-ree small animal imaging of biologically functional molecules.