Skip to main content

Research Repository

Advanced Search

π‐Expanded Thioxanthones ‐ Engineering the Triplet Level of Thioxanthone Sensitizers for Lanthanide‐Based Luminescent Probes with Visible Excitation

Dansholm, Charlotte Nybro; Junker, Anne Kathrine R.; Nielsen, Lea G.; Kofod, Nicolaj; Pal, Robert; Sørensen, Thomas Just

π‐Expanded Thioxanthones ‐ Engineering the Triplet Level of Thioxanthone Sensitizers for Lanthanide‐Based Luminescent Probes with Visible Excitation Thumbnail


Authors

Charlotte Nybro Dansholm

Anne Kathrine R. Junker

Lea G. Nielsen

Nicolaj Kofod

Thomas Just Sørensen



Abstract

Bright lanthanide based probes for optical bioimaging must rely on the antenna principle, where the lanthanide‐centred excited state is formed by a complex sensitization process. Efficient sensitization of lanthanide‐centred emission occurs via triplet states centred on the sensitizing chromophore. Here, the triplet state of thioxanthone chromophores is modulated by extending the π‐system. Three thioxanthone chromophores‐thioxanthone, benzo[c]thioxanthone, and naphtho[2,3‐c]thioxanthone were synthesised and characterised. The triplet state energies and lifetimes is found to change as expected, and two dyes are found to be suitable sensitizers for europium(iii) luminescence. Reactive derivatives of thioxanthone and benzo[c]thioxanthone were prepared and coupled to a 1,4,7,10‐tetraazacyclododecane‐1,4,7‐triacetic acid (DO3A) lanthanide binding pocket. The photophysics and the performance in optical bioimaging of the resulting europium(iii) complexes were investigated. It is concluded that while the energetics favour efficient sensitization, the solution structure does not. While it was found that the complexes are too lipophilic to be efficient luminescent probes for optical bioimaging, we successfully demonstrated bioimaging using europium(iii) luminescence following 405 nm excitation.

Citation

Dansholm, C. N., Junker, A. K. R., Nielsen, L. G., Kofod, N., Pal, R., & Sørensen, T. J. (2019). π‐Expanded Thioxanthones ‐ Engineering the Triplet Level of Thioxanthone Sensitizers for Lanthanide‐Based Luminescent Probes with Visible Excitation. ChemPlusChem, 84(12), 1778-1788. https://doi.org/10.1002/cplu.201900309

Journal Article Type Article
Online Publication Date Jun 17, 2019
Publication Date Dec 31, 2019
Deposit Date Aug 15, 2019
Publicly Available Date Jul 8, 2020
Journal ChemPlusChem
Electronic ISSN 2192-6506
Publisher Wiley
Peer Reviewed Peer Reviewed
Volume 84
Issue 12
Pages 1778-1788
DOI https://doi.org/10.1002/cplu.201900309
Public URL https://durham-repository.worktribe.com/output/1295915

Files

Accepted Journal Article (678 Kb)
PDF

Copyright Statement
This is the accepted version of the following article: Dansholm, Charlotte Nybro, Junker, Anne Kathrine R., Nielsen, Lea G., Kofod, Nicolaj, Pal, Robert & Sørensen, Thomas Just (2019). π‐Expanded Thioxanthones ‐ Engineering the Triplet Level of Thioxanthone Sensitizers for Lanthanide‐Based Luminescent Probes with Visible Excitation. ChemPlusChem 84(12): 1778-1788, which has been published in final form at https://doi.org/10.1002/cplu.201900309. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for self-archiving.






You might also like



Downloadable Citations