In Vivo Antitumor Efficacy Analysis of PDT: A Technique to Determine the Phototoxic Potential of a Photosensitizer in Tumor Bearing Mice

- Photodynamic therapy or PDT is a light-based treatment involving photosensitizer molecules. These molecules are activated by lights of specific wavelengths and convert molecular oxygen present in cells to reactive oxygen species that induce cell death. To begin, develop a lung tumor-bearing mouse model by injecting the appropriate concentration of lung cancer cell suspension into the lower flank of an anesthetized mouse. Monitor until a tumor grows to an appropriate volume.

Subsequently, prepare a suspension of the desired photosensitizer loaded in a lung cancer targeted nanoparticle-based delivery system. Inject this suspension into the tail vein of an anesthetized tumor-bearing mouse. Provide sufficient time for the photosensitizer containing nanoparticles to reach the tumor site and enter the cancer cells.

Next, anesthetize the mouse. Position a PDT laser at an optimal distance above the tumor to ensure uniform illumination of its entire volume. Irradiate the tumor at an appropriate wavelength for the desired time. Maintain the mouse within a cage in the dark for 24 hours. Monitor the day-to-day changes to the tumor volume. Irradiated tumor-bearing mice injected with the photo