Structure–Property Relationships of Near-Infrared Cyanine Dyes: Chalcogen-Driven Singlet Oxygen Generation with High Fluorescence Efficiency
We report the design, synthesis, and optical characterisations of eight novel near-infrared (NIR) cyanine dyes incorporating different chalcogens (O, S, and Se). These dyes exhibited excellent deep-NIR absorption (λ<sub>max</sub> = 767-833 nm) and emission (λ<sub>max</sub> = 784-859 nm) profiles. TDDFT calculations matched well the experimental trends and data. All compounds exhibited high extinction coefficients (178,000-267,000 cm<sup>-1</sup> M<sup>-1</sup>) and good fluorescence quantum yields, resulting in high overall brightnesses. Remarkably, the selenium-containing dyes featuring terminal indole and benzoindole-type units exhibited impressive singlet oxygen quantum yields of around 13%, a standout performance in the deep-NIR region. These values are particularly promising and highlights the potential of these dyes for deep-NIR imaging and photodynamic applications.
Authors
- Mark Philip Bradley (ORCID: https://orcid.org/0000-0002-6473-7111)
- Shufan Yang (ORCID: https://orcid.org/0009-0006-1964-3155)
- Annamaria Lilienkampf (ORCID: https://orcid.org/0000-0002-3593-0393)
- Ewan Forsyth (ORCID: https://orcid.org/0000-0001-6694-1231)
- Devis Di Tommaso (ORCID: https://orcid.org/0000-0002-4485-4468)
- Rachel Crespo-Otero
- Kerry Setchfield
- Wuyang Lin
- Amanda Wright
Institutions
- Mansfield University (US)
- University of Nottingham (GB)
- Queen Mary University of London (GB)
- University of Oxford (GB)
- University College London (GB)
- University of Edinburgh (GB)
Publication Details
- Journal
- ACS Omega
- Published
- 2026-01-12
- DOI
- https://doi.org/10.1021/acsomega.5c10499
- Primary Topic
- Nanoplatforms for cancer theranostics
- Type
- article
- Field-Weighted Citation Impact
- 0.00