Published online Nov 28, 2023. doi: 10.4329/wjr.v15.i11.315
Peer-review started: October 3, 2023
First decision: October 17, 2023
Revised: October 26, 2023
Accepted: November 17, 2023
Article in press: November 17, 2023
Published online: November 28, 2023
Processing time: 51 Days and 15.9 Hours
Radionuclides produce Cherenkov radiation (CR), which can potentially activate photosensitizers (PSs) in phototherapy. Several groups have studied Cherenkov energy transfer to PSs using optical imaging; however, cost-effectively identifying whether PSs are excited by radionuclide-derived CR and detecting fluorescence emission from excited PSs remain a challenge. Many laboratories face the need for expensive dedicated equipment.
To cost-effectively confirm whether PSs are excited by radionuclide-derived CR and distinguish fluorescence emission from excited PSs.
The absorbance and fluorescence spectra of PSs were measured using a micro
The maximum absorbance of TCPP was at 390–430 nm, and the emission peak was at 670 nm. The CR and CR-induced TCPP emissions were observed using the optical imaging system and the high-transmittance long-pass filters described above. The emission spectra of TCPP with a peak in the 645–700 nm window were obtained by calculation and subtraction based on the serial signal intensity (total flux) difference between 64CuCl2 + TCPP and
This simple method identifies the PS fluorescence emission generated by radionuclide-derived CR and can contribute to accelerating the development of Cherenkov energy transfer imaging and the discovery of new PSs.
Core Tip: Radionuclides produce Cherenkov radiation (CR), which can potentially activate photosensitizers (PSs) in phototherapy. However, a cost-effective method to determine whether radionuclide-derived CR excites PSs and the measurement of fluorescence emitted by excited PS remain elusive. We propose a cost-effective method using a charge-coupled device optical imaging system combined with long-pass filters and subtraction image processing to distinguish CR and PS fluorescence emission. As a proof-of-concept, 64CuCl2 and the PS tetrakis (4-carboxyphenyl) porphyrin were used in the experiments. This method can contribute to accelerating the development of Cherenkov energy transfer imaging and the discovery of new PSs.