The synthesis, photophysical characterization, and determination of singlet oxygen quantum yields (ΦΔ) for a class of fluorene derivatives with potential application in two-photon photodynamic therapy (PDT) is reported. It has been demonstrated that these compounds possess the ability to generate singlet oxygen (1O2) upon excitation. A photochemical method, using 1,3-diphenylisobenzofuran (DPBF) as 1O2 chemical quencher, was employed to determine the singlet oxygen quantum yields (ΦΔ) of the fluorene-based photosensitizers in ethanol. ΦΔ values ranged from 0.35 to 0.75. These derivatives may have potential application as two-photon photosensitizers when pumped via two-photon excitation in the near-IR spectral region.
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ACKNOWLEDGMENTS
The authors acknowledge the Research Corporation, the donors of the Petroleum Research Fund of the American Chemical Society, and the Florida Hospital Gala Endowed Award for Oncologic Research for support. Dr. Mykhailo V. Bondar and Mr. Erwan Baleine are gratefully acknowledged for helpful discussions.
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Belfield, K.D., Corredor, C.C., Morales, A.R. et al. Synthesis and Characterization of New Fluorene-Based Singlet Oxygen Sensitizers. J Fluoresc 16, 105–110 (2006). https://doi.org/10.1007/s10895-005-0008-1
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DOI: https://doi.org/10.1007/s10895-005-0008-1