Photochemistry of Common Xanthene Fluorescent Dyes as Efficient Visible-light Activatable CO-Releasing Molecules

Authors

  • Marek Martínek RECETOX, Masaryk University ,
  • Lucie Ludvíková RECETOX, Masaryk University ,
  • Mária Šranková 1st Faculty of Medicine, Charles University & General University Hospital, Charles University ,
  • Rafael Navrátil Faculty of Science, Charles University ,
  • Lucie Muchová 1st Faculty of Medicine, Charles University & General University Hospital, Charles University ,
  • Jiří Huzlík Transport Research Centre (CDV) ,
  • Libor Vítek 1st Faculty of Medicine, Charles University & General University Hospital, Charles University ,
  • Petr Klán RECETOX, Masaryk University & Department of Chemistry, Masaryk University ,
  • Peter Šebej RECETOX, Masaryk University

Abstract

Xanthene derivatives are organic dyes, some of which are routinely used in different chemical and biological applications, including human medicine. In this work, we investigated the photochemistry of some of the most common ones, fluorescein, eosin Y, and rose bengal, and major products of their photodegradation using optical spectroscopy, NMR, chromatography and mass spectroscopy techniques. These substances, usually considered (photo)chemically stable, were found to liberate carbon monoxide (CO) in 40–80% chemical yields upon extensive irradiation with visible light in aqueous solutions during their multistep concomitant degradation processes. In addition, a number of low-mass secondary photoproducts, such as phthalic and formic acids, were identified in the irradiated mixtures. We demonstrate that these common fluorescent dyes can also be considered as visible-light activatable carbon monoxide (CO)-releasing molecules (photoCORMs) under specific conditions with potential biological implications.

Content

Supplementary material

Supporting Information
Supporting information contents materials and methods, synthetic details, photophysical properties of fluorophores, details on analytical methods, MS, NMR, UV/vis, fluorescence spectra, solubility of CO, stability determination experiments, details on thermogravimetric analyses, photodisociation spectroscopy.