Imaging assessment of photosensitizer emission induced by radionuclide-derived Cherenkov radiation using charge-coupled device optical imaging and long-pass filters

Figure 1 Schematic diagram of the optical imaging approach used to detect Cherenkov optical emission and to separate the fluorescence emission of tetrakis (4-carboxyphenyl) porphyrin induced by Cherenkov optical emission. A: Long-pass filters step-cut the Cherenkov light, allowing the separation of tetrakis (4-carboxyphenyl) porphyrin (TCPP) emission; B: The Cherenkov light emitted from the radionuclide was gradually cut off with the appropriate long-pass filters of different wavelengths. The blue and orange curves are schematic representations of the Cherenkov optical emission and TCPP fluorescence spectra, respectively. CCD: Charge-coupled device optical imaging system.