Abstract
The response of a given cell to spatially-resolved sub-cellular irradiation of a singlet oxygen photosensitizer (protoporphyrin
IX, PpIX) using a focused laser was assessed. In these experiments, incident light was scattered over a volume greater than
that defi ned by the dimensions of the laser beam as a consequence of the inherent inhomogeneity of the cell. Upon irradiation
at a wavelength readily absorbed by PpIX in a one-photon transition, this scattering of light eliminated any advantage
accrued to the use of focused irradiation. However, upon irradiation at a longer wavelength where PpIX can only absorb light
under non-linear two-photon conditions, meaningful intracellular resolution was achieved in the small spatial domain where
the light intensity was high enough for absorption to occur.
IX, PpIX) using a focused laser was assessed. In these experiments, incident light was scattered over a volume greater than
that defi ned by the dimensions of the laser beam as a consequence of the inherent inhomogeneity of the cell. Upon irradiation
at a wavelength readily absorbed by PpIX in a one-photon transition, this scattering of light eliminated any advantage
accrued to the use of focused irradiation. However, upon irradiation at a longer wavelength where PpIX can only absorb light
under non-linear two-photon conditions, meaningful intracellular resolution was achieved in the small spatial domain where
the light intensity was high enough for absorption to occur.
| Original language | English |
|---|---|
| Journal | Free Radical Research |
| Volume | 44 |
| Pages (from-to) | 1383-1397 |
| ISSN | 1071-5762 |
| Publication status | Published - 2010 |