Photodynamic therapy in 2D and 3D human cervical carcinoma cell cultures employing LED light sources emitting at different wavelengths.

Light of different wavelengths can be used to obtain a more profitable outcome of photodynamic therapy (PDT), according to the absorption bands of the photosensitizer (PS). Low-grade cervical intraepithelial neoplasias (CINs) are superficial lesions that can be treated with light of shorter wavelength than red because a large light penetration depth in tissue is not necessary. We report a comparative investigation performed to evaluate the efficacy of light-emitting diodes (LEDs) of different wavelengths in the photodynamic treatment applied to both 2D and 3D HeLa cell spheroid cultures.

Photodynamic therapy in fibrosarcoma BALB/c animal model: Observation of the rebound effect.

In vivo spectrofluorometric analysis during photodynamic therapy (PDT) is a fundamental tool to obtain information about drug bleaching kinetics. Using a portable spectrofluorometer with an excitation source emitting at 400nm wavelength and a spectral analyzer ranging from 500nm to 800nm, the evolution of the meta-tetra(hydroxyphenyl) chlorin (m-THPC) photosensitizer fluorescence spectrum at the tumoral tissue of BALB/c murines with fibrosarcoma located at their flank was followed up. Ex vivo fluorescence measurements of the tumor and skin were also performed with the aim of better characterizing the in vivo signal at different parts of the tumor.