Collisional quenching of erythrosine B as a potential reference dye for impulse response function evaluation.
We studied the collisional quenching of the erythrosine B fluorophore by potassium iodide. The quenching follows a Stern-Volmer dependence up to the highest quencher concentration. The lifetime of erythrosine B decreases to 24 ps in 5.02 M of potassium iodide. The quantum yield of erythrosine B in the presence of 5.02 M KI is 0.0035. The relatively high brightness makes this compound attractive as an ultrashort reference in time-resolved measurements. In both frequency- and time-domain fluorescence techniques, there is a need for lifetime standards with extremely short decay times. Mimicking the instantaneous scattering at longer wavelengths allows color-effect-free measurements in the emission region. Another motivation is the problem of obtaining the impulse response function in the case of two-photon excitation. Time-resolved microscopy also benefits from fast-decaying dyes because the impulse response function can be evaluated at the emission wavelength of the investigated specimen without changing filters. We demonstrated that impulse response functions for commonly used detectors are practically the same for scattering as for quenched erythrosine B emission. We also analyzed a complex fluorescence decay using both elastic scattering and quenched erythrosine B emission as a response function.
Szabelski
Mariusz
M
Center for Commercialization of Fluorescence Technologies, Department of Molecular Biology and Immunology, UNT HSC, Fort Worth, Texas, USA. fizmsz@univ.gda.pl
Ilijev
Douglas
D
Sarkar
Pabak
P
Luchowski
Rafal
R
Gryczynski
Zygmunt
Z
Kapusta
Peter
P
Erdmann
Rainer
R
Gryczynski
Ignacy
I
D000465:Algorithms; D004923:Erythrosine / Q000032:analysis* / Q000737:chemistry* / Q000592:standards; D005240:Feasibility Studies; D005456:Fluorescent Dyes / Q000032:analysis* / Q000737:chemistry* / Q000592:standards; D011193:Potassium Iodide / Q000737:chemistry*; D012016:Reference Values; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D013050:Spectrometry, Fluorescence / Q000379:methods* / Q000592:standards
D005456:Fluorescent Dyes; D011193:Potassium Iodide; D004923:Erythrosine