Red-to-blue triplet: triplet annihilation upconversion for calcium sensing

Andreeva, V.D.; Regeni, I.; Yang, T.; Elmanova, A.; Presselt, M.; Dietzek-Ivansic, B.; Bonnet, S.A. (2024)

Article / Letter to editor

Triplet-triplet annihilation upconversion is a bimolecular process converting low-energy photons into high-energy photons. Here, we report a calcium-sensing system working via triplet-triplet annihilation (TTA) upconverted emission. The probe itself was obtained by covalent conjugation of a blue emitter, perylene, with a calcium-chelating moiety, and it was sensitized by the red-light-absorbing photosensitizer palladium(II) tetraphenyltetrabenzoporphyrin (PdTPTBP). Sensing was selective for Ca²⁺ and occurred in the micromolar domain. In deoxygenated conditions, the TTA upconverted luminescence gradually appeared upon adding an increasing concentration of calcium ions, to reach a maximum upconversion quantum yield of 0.0020.

• All authors: Andreeva, V.D.; Regeni, I.; Yang, T.; Elmanova, A.; Presselt, M.; Dietzek-Ivansic, B.; Bonnet, S.A.
• Date: 2024-07-15
• Journal: Journal of Physical Chemistry Letters
• Volume: 15
• Pages: 7430 - 7435
• DOI: doi:10.1021/acs.jpclett.4c01528