Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 1996 Jun;70(6):2959-68.
doi: 10.1016/S0006-3495(96)79866-1.

Influence of the triplet excited state on the photobleaching kinetics of fluorescein in microscopy

L Song  1 , C A Varma, J W Verhoeven, H J Tanke
Affiliations

Influence of the triplet excited state on the photobleaching kinetics of fluorescein in microscopy

L Song et al. Biophys J. 1996 Jun.

Abstract

The investigation in this report aimed at providing photophysical evidence that the long-lived triplet excited state plays an important role in the non-single-exponential photobleaching kinetics of fluorescein in microscopy. Experiments demonstrated that a thiol-containing reducing agent, mercaptoethylamine (MEA or cysteamine), was the most effective, among other commonly known radical quenchers or singlet oxygen scavengers, in suppressing photobleaching of fluorescein while not reducing the fluorescence quantum yield. The protective effect against photobleaching of fluorescein in the bound state was also found in microscopy. The antibleaching effect of MEA let to a series of experiments using time-delayed fluorescence spectroscopy and nanosecond laser flash photolysis. The combined results showed that MEA directly quenched the triplet excited state and the semioxidized radical form of fluorescein without affecting the singlet excited state. The triplet lifetime of fluorescein was reduced upon adding MEA. It demonstrated that photobleaching of fluorescein in microscopy is related to the accumulation of the long-lived triplet excited state of fluorescein and that by quenching the triplet excited state and the semioxidized form of fluorescein to restore the dye molecules to the singlet ground state, photobleaching can be reduced.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Photochem Photobiol. 1972 Oct;16(4):305-14 - PubMed
    1. Biochim Biophys Acta. 1974 Nov 15;367(3):282-94 - PubMed
    1. Biophys J. 1976 Sep;16(9):1055-69 - PubMed
    1. Proc Natl Acad Sci U S A. 1979 Jul;76(7):3314-7 - PubMed
    1. Biophys J. 1995 Jun;68(6):2588-600 - PubMed

LinkOut - more resources

-