In Search for the Best Environment for Single Molecule Studies: Photostability of Single Terrylenediimide Molecules in Various Polymer Matrices

Abstract

Photobleaching is the main limiting factor in single molecule studies by optical techniques. We investigated the dependence of photostability of terrylene diimide (TDI) derivative on its environment using confocal fluorescence microscopy. Seven different polymers were tested. Depending on the matrix, photobleaching quantum yields vary by 2 orders of magnitude. Their values correlate with parameters characterizing oxygen mobility in polymers: diffusion coefficient and permeability. Poly(vinyl chloride) (PVC) and poly(methyl methacrylate) (PMMA) exhibit the lowest photodestruction quantum yields. Additional enhancement of photostability can be achieved by aging of PVC or by flushing the sample with nitrogen, which confirms the involvement of oxygen in photodestruction. Different character of the time traces of the intensity of emission from single TDI molecules is observed for different polymer matrices, ranging from intense blinking in the least stable polycarbonate, to practically no blinking in the most stable PVC. These results suggest a photodegradation mechanism involving self-sensitized photooxidation in oxygen complexes of TDI.

Effect of molecular side groups and local nanoenvironment on photodegradation and its reversibility

“…The corresponding average "on" times are then 42 sec, 35 sec, and 29 sec, respectively, which are consistent with differences in oxygen permeability and diffusion coefficients in these matrices, with, for example, PMMA having these parameters lower than PS by more than an order of magnitude, which renders it a much better matrix for single-molecule fluorescence spectroscopy. 21 Additionally, the percentage of molecules that exhibit blinking (i.e. reversible as opposed to irreversible degradation at the 100 sec time scale of the experiment) increased from 13% in PMMA to 20% in PS.…”

Towards More Photostable, Brighter, and Less Phototoxic Chromophores: Synthesis and Properties of Porphyrins Functionalized with Cyclooctatetraene

“…For single‐molecule fluorescence studies in polymer films, choosing an appropriate environment is crucial. It was demonstrated that photodegradation quantum yields of terrylene diimide vary by two orders of magnitude depending on the polymer matrix [13] . The highest photostability was observed for polymers that exhibit the lowest oxygen mobility.…”

Ceria/polymer nanocontainers for high-performance encapsulation of fluorophores

“…This dye belongs to the rylene family [28], which is formed by extending the π-conjugated core system of highly fluorescent perylene-3,4:9,10-tetracarboxdimides. The rylene dyes have unique optical properties, such as high extinction coefficients, high thermal, chemical and photochemical stabilities, and exhibit brilliant colors [29–30]. Furthermore, in bulk samples, TDI demonstrates an excellent fluorescence quantum yield (ca.…”