Photon energy upconversion in porphyrins: one-photon hot-band absorption versus two-photon absorption

Drobizhev, Mikhail; Karotki, Aliaksandr; Kruk, M. M.; Krivokapić, Alexander; Anderson, Harry L.; Rebane, Aleksander

doi:10.1016/s0009-2614(03)00162-3

Cited by 73 publications

(65 citation statements)

References 32 publications

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“…The slight increase of the TPA cross section at 780 nm of TPA-FxP is due to the contribution from the excitation of both the conjugated peripheral oligofluorene arms and the porphyrin core. The TPA cross section value about 3360 GM of TPA-FxP at this wavelength is comparable to the highest values reported from other chemically modified porphyrin molecules [17][18][19][20][21][22][23][24][25][26][27][28][29][30]42] . Compared with those of the chemically modified porphyrin molecules with through-space interactions [26][27][28][29][30] , the FRET efficiency within TPA-FxP is slightly lower, but the TPA cross section of TPA-FxP is much larger, indicating that the through-bond interaction could also contribute efficiently to the enhancement of the TPA cross section of TPA-FxP.…”

Section: Two-photon Excitation Fluorescence Spectrasupporting

confidence: 84%

Enhancement of two-photon absorption cross section and singlet-oxygen generation in porphyrin-cored star polymers

Yan

Jia

et al. 2009

Sci. China Ser. B-Chem.

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We report a newly synthesized polymer of a star-shaped porphyrin compound (TPA-FxP) with four oligofluorene arms at its meso positions with the pronounced enhancement of the two-photon properties and the generation of singlet oxygen by utilizing the two-photon excited fluorescence resonance energy transfer. The steady-state spectra and transient triplet-triplet absorption spectra give evidence that the enhanced two-photon absorption cross section results from not only the through-space energy transfer (Förster) but also the through-bond energy transfer between conjugated peripheral oligofluorene arms and the porphyrin core. The two-photon absorption cross section at 780 nm up to 3360 GM (1 GM = 10 −50 cm 4 ⋅s/photon) of TPA-FxP was obtained, which is comparable to the highest values reported from other similar chemically modified porphyrin core compounds. Furthermore, the enhanced production of singlet oxygen under two-photon absorption conditions is also reported.porphyrin-cored star polymer, two-photon excitation, energy transfer

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Section: Two-photon Excitation Fluorescence Spectrasupporting

confidence: 84%

Enhancement of two-photon absorption cross section and singlet-oxygen generation in porphyrin-cored star polymers

Yan

Jia

et al. 2009

Sci. China Ser. B-Chem.

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“…Such absorption arises due to transitions from thermally activated vibrational levels in the ground electronic state (hot-band transitions; ref. 35).…”

Section: Resultsmentioning

confidence: 99%

New Two-Photon Activated Photodynamic Therapy Sensitizers Induce Xenograft Tumor Regressions after Near-IR Laser Treatment through the Body of the Host Mouse

Starkey¹,

Rebane

Drobizhev³

et al. 2008

Clinical Cancer Research

225

189

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Purpose: The aim of this study was to show that novel photodynamic therapy (PDT) sensitizers can be activated by two-photon absorption in the near-IR region of the spectrum and to show, for the first time, that such activation can lead to tumor regressions at significant tissue depth. These experiments also evaluated effects of high-energy femtosecond pulsed laser irradiation on normal tissues and characterized the response of xenograft tumors to our PDT protocols. Experimental Design: Human small cell lung cancer (NCI-H69), non-small cell lung cancer (A549), and breast cancer (MDA-MB-231) xenografts were induced in SCID mice. Irradiation of sensitized tumors was undertaken through the bodies of tumor-bearing mice to give a treatment depth of 2 cm. Posttreatment tumor regressions and histopathology were carried out to determine the nature of the response to these new PDT agents. Microarray expression profiles were conducted to assess the similarity of responses to single and two-photon activated PDT. Results:Regressions of all tumor types tested were seen. Histopathology was consistent with known PDT effects, and no, or minimal, changes were noted in irradiated normal tissues. Cluster analysis of microarray expression profiling showed reproducible changes in transcripts associated with apoptosis, stress, oxygen transport, and gene regulation. Conclusions: These new PDT sensitizers can be used at a depth of 2 cm to produce excellent xenograft regressions. The tumor response was consistent with known responses to singlephoton activated PDT. Experiments in larger animals are warranted to determine the maximal achievable depth of treatment.Photodynamic therapy (PDT; ref. 1) is a protocol that uses light of the appropriate wavelength to activate photosensitizer accumulated in tumor tissue to its triplet state (2). The triplet excitation energy can be effectively transferred to molecular oxygen, resulting in the generation of singlet oxygen, superoxide radical, and other active oxygen species (2, 3). The singlet oxygen causes direct chemical damage to tumor and/or tumor endothelial cells (4), initiates a neutrophilic inflammatory response (5), and can stimulate both innate and specific antitumor immune responses (6 -8). Singlet-oxygen production, however, requires a sufficiently high energy of the triplet state of the sensitizer. Long-wavelength near-IR (NIR) light k ex > 750 nm has relatively low-photon energy, which restricts the range of processes that can be activated by one-photon excitation. The relation between the wavelength and the minimum excitation energy of singlet oxygen is shown in Fig. 1A. The dark gray shaded area corresponds to the excitation energy below the required minimum value, E so < 1.5 -1.6 eV (9, 10), which shows that sensitization by one-photon absorption (1PA) fails in the phototherapeutic window 780 to 950 nm, where tissues have maximum transparency to light. Sensitization by simultaneous two-photon absorption (2PA; ref. 11) combines the energy of two photons and can provide suffi...

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“…[48] A fully quadratic dependence of the fluorescence intensity on the excitation power was observed for each sample at all wavelengths of the spectra shown in Figures 3 and 4, indicating that the obtained cross-sections are only due to 2PA. The very high "apparent" 2PA cross-sections obtained at lower wavelengths were not taken into account and are not reported here, as concomitant deviation from quadraticity was observed, indicating the beginning of hot-band absorption [49] and/or 1PA resonance.…”

Section: Two-photon Absorptionmentioning

confidence: 89%

Fluorenyl porphyrins for combined two-photon excited fluorescence and photosensitization

Mongin

Hugues

Blanchard‐Desce

et al. 2015

Chemical Physics Letters

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The two-photon absorption (2PA), the luminescence and the photosensitization properties of porphyrin-cored fluorenyl dendrimers and meso-substituted fluorenylporphyrin monomer, dimer and trimer are described. In comparison with model tetraphenylporphyrin, these compounds combine enhanced (non-resonant) 2PA cross-sections in the near infrared and enhanced fluorescence quantum yields, together with maintained singlet oxygen generation quantum yields. "Semi-disconnection" between fluorenyl groups and porphyrins (i.e. direct meso substitution) proved to be more efficient than non-conjugated systems (based on efficient FRET between fluorenyl antennae and porphyrins). These results are of interest for combined two-photon imaging and photodynamic therapy.

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Photon energy upconversion in porphyrins: one-photon hot-band absorption versus two-photon absorption

Cited by 73 publications

References 32 publications

Enhancement of two-photon absorption cross section and singlet-oxygen generation in porphyrin-cored star polymers

Enhancement of two-photon absorption cross section and singlet-oxygen generation in porphyrin-cored star polymers

New Two-Photon Activated Photodynamic Therapy Sensitizers Induce Xenograft Tumor Regressions after Near-IR Laser Treatment through the Body of the Host Mouse

Fluorenyl porphyrins for combined two-photon excited fluorescence and photosensitization

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