Sodium Green as a potential probe for intracellular sodium imaging based on fluorescence lifetime.
Anal Biochem
; 250(2): 131-8, 1997 Aug 01.
Article
in En
| MEDLINE
| ID: mdl-9245429
ABSTRACT
We characterized the use of the fluorescent probe Sodium Green for measurements of intracellular free sodium using frequency-domain, phase-modulation fluorometry. The intensity decays were found to be strongly Na+ dependent, with mean lifetime increasing from 1.13 ns in the absence of Na+ to 2.39 ns in the presence of 140 mM Na+. Detailed analysis of the intensity decays in the presence of Na+ and K+ in the concentration range from 0 to 500 mM is provided. Sodium sensing using data measured at a single modulation frequency is described. Phase and modulation data showed high sensitivity to Na+ and substantially lower sensitivity to K+. Additionally, exposure of Sodium Green to intense illumination indicated that Sodium Green is much more photostable than its precursor, fluorescein. These results indicate that lifetime-based measurements with Sodium Green can be used for imaging of intracellular free [Na+] in the range from about 0.5 to 50 mM with high accuracy.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Sodium
/
Fluorescent Dyes
Language:
En
Journal:
Anal Biochem
Year:
1997
Document type:
Article
Affiliation country:
United States