Journal
METHODS AND APPLICATIONS IN FLUORESCENCE
Volume 9, Issue 3, Pages -Publisher
IOP Publishing Ltd
DOI: 10.1088/2050-6120/abfcac
Keywords
photostability; single molecules; porphycene; fluorescence; photobleaching
Categories
Funding
- Foundation for Polish Science [HOMING/2017-4/32, POIR.04.04.00-00-42E8/17-00]
- National Science Center [2019/35/D/ST5/00958]
- Polish National Science Center [2016/22/A/ST4/00029]
Ask authors/readers for more resources
The study of single molecule photobleaching using confocal fluorescence microscopy reveals that substitution of porphycene with bulky tert-butyl groups enhances photostability, while the presence of oxygen around the molecule increases the efficiency of physical quenching of the chromophore triplet state. The distribution of photodegradation quantum yields suggests that physical and chemical quenching rates exhibit different distance and orientation dependences.
Photobleaching of single molecules has been studied using confocal fluorescence microscopy for porphycene, a porphyrin isomer, and its two derivatives. Fourfold substitution of porphycene with bulky tert-butyl groups leads to the enhancement of photostability, even though the spectral, photophysical, and redox parameters remain similar. We attribute this effect to the increase of the efficiency of physical quenching of the chromophore triplet state by oxygen, compared with the yield of chemical reaction that leads to photobleaching. Analysis of the observed photon fluxes from single emitters embedded in a polymer film shows that the experiment based on fluorescence is biased towards detection of molecules which have oxygen-the triplet quencher-in their vicinity. The distribution of the measured photodegradation quantum yields is very heterogeneous, suggesting that physical and chemical quenching rates exhibit different distance and orientation dependences.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available