Two-photon spectroscopic behaviors and photodynamic effect on the BEL-7402 cancer cells of the new chlorophyll photosensitizer

Abstract

The spectroscopic properties of a new chlorophyll derivate photosensitizer (CDP) are studied under the excitation wavelengths at 800 and 400 nm using femtosecond pulses from a Ti: sapphire laser. The damaging effect of CDP on the BEL-7402 cancer cells is also investigated upon two-photon illumination at 800 nm. The normalized fluorescence spectra of CDP in tetrahydrofuran (THF) show that two-photon and one-photon spectra have the same distributions and the same emission bands (675 nm). The lifetimes of two-and one-photon induced fluorescence of this molecule are of the order of 5.0 ns. By comparing the data it is shown that there is some difference between the two lifetimes, but the difference is less than one nanosecond. The two-photon absorption cross section of the molecule is also measured at 800 nm and estimated as about V ƍ 2 § 31.5×10 50 cm 4 ·s·photon 1 . The results of two-photon photodynamic therapy (TPPDT) tests show that CDP can kill all of the tested cancer cells according to the usual Eosine assessment. Our results indicate that the two-photon-induced photophysical, photochemical and photosensitizing processes of CDP may be basically similar to those of one-photon excitation. These behaviors of the sample suggest that one may find other possible methods to estimate some photosensitizers' effects in details such as their distribution in cells and the reactive targets of the sub-cellular parts of some tumor cells via two-photon excitation techniques. photosensitizer, chlorophyll derivate, two-photon fluorescence, two-photon absorption cross-section, TPPDT, BEL-7402 cell

Molecular photosensitisers for two-photon photodynamic therapy

“…The commercialisation of femtosecond (fs) NIR Ti: sapphire lasers in the 1990's facilitated and encouraged TP-PDT experiments. Onephoton PSs were used such as meso-tetrahydroxyphenylchlorin (m-THPC), 65 Photofrin ® , 55, 56 5-aminolevulinic acid (ALA)-induced protoporphyrin IX, 66 a chlorophyll-based PS 67 and more recently sulfonated aluminum phthalocyanine, 59 and pyropheophorbide-a methyl ester (MPPa). , respectively (Fig.…”

Multifunctional Magnetic Materials of Organic Origin for Biomedical Applications: A Theoretical Study

“…The TPA cross‐sections of existing photosensitizers are in the order of 1–100 GM . In a recent report Zhao et al . studied the spectroscopic properties of Chlorophyll derivative photosensitizer (CDP) and their TPA cross section is measured as 31.5 GM.…”

Two-photon absorption coefficient in relation to the typical pulse models of laser

“…(18) (or Eq. (6)), the molecular TPA cross-section r 2 (in units of cm 4 /GW) or r 0 2 (in units of cm 4 s/photon) can be determined by using the following relationships [36,37]…”

“…(7) is, sometimes, used as the basic formula to obtain the TPA coefficient of some materials in nonlinear transmission measurements [36,37,39]. However, we find that, for a set of energy transmission data, b 0 obtained based on Eq.…”