Related Experiment Video
Updated: Feb 12, 2026

Detection of Bacteria Using Fluorogenic DNAzymes
Published on: May 28, 2012
Intramolecular substitution uncages fluorogenic probes for detection of metallo-carbapenemase-expressing bacteria
Aiguo Song1, Yunfeng Cheng1, Jinghang Xie1
1Molecular Imaging Program at Stanford , Departments of Radiology and Chemistry , Stanford University , 1201 Welch Road , Stanford , CA 94305-5484 , USA .
Abstract:
This work reports a novel caging strategy for designing fluorogenic probes to detect the activity of β-lactamases. The caging strategy uses a thiophenyl linker connected to a fluorophore caged by a good leaving group-dinitrophenyl. The uncaging proceeds in two steps through the sulfa-releasing and subsequent intramolecular substitution. The length of the linker has been examined and optimized to maximize the rate of intramolecular reaction and thus the rate of fluorescence activation. Finally based on this strategy, we prepared a green fluorogenic probe CAT-7 and validated its selectivity for detecting metallo-carbapenemases (VIM-27, IMP-1, NDM-1) in carbapenem-resistant Enterobacteriaceae (CRE) lysates.
Related Concept Videos
Intermolecular vs Intramolecular Forces
Coordination of Gene Expression Processes in Bacteria
Intramolecular Aldol Reaction
Radical Reactivity: Intramolecular vs Intermolecular
Trigonometric Substitution
Rationalizing Substitutions

