pH fluorescent probes: chlorinated fluoresceins
Related Experiment Video
Updated: Jul 8, 2026

Visualization of Bacterial Resistance using Fluorescent Antibiotic Probes
Published on: March 2, 2020
1College of Chemistry and Chemical Engineering, Donghua University, Shanghai, People's Republic of China. fyge@dhu.edu.cn
Abstract:
A series of regiospecific chlorinated fluoresceins have been synthesized by the reaction of the regiospecific chlorinated resorcinols with chlorinated phthalic anhydride. The regioisomers were successfully separated by chromatography. The photophysical properties of the obtained chlorinated fluoresceins were examined and found their absorption and emission maxima at long wavelength with high fluorescence quantum yield. Especially, pH-dependent properties of chlorinated fluoresceins have been studied in detail. These compounds show strongly pH-sensitive range of 3.5-7.0, and have lower pK (a) values than fluorescein. Furthermore, their fluorescent intensity could reach the maximum in the physiological environment of pH range 6.8-7.4. Due to higher fluorescence quantum yield and lower pK (a) values, chlorinated fluoresceins will be expected to be used as excellent pH fluorescent probes for pH measurement of the acidic cell.
Related Concept Videos
Labeling DNA Probes
Radioisotopes, fluorophores, or small molecule binding partners like biotin or digoxigenin, are the most widely used reporter tags for labeling DNA probes. These labels can be attached to the probe DNA molecule via...
FISH - Fluorescent In-situ Hybridization
Immunofluorescence Microscopy
The...

