Theoretical and experimental characterization of emission and transmission spectra of Cerenkov radiation generated by (177)Lu in tissue

Cerenkov radiation (CR) is the emission of UV-vis light generated by the de-excitation of the molecules in the medium, after being polarized by an excited particle traveling faster than the speed of light. When [Formula: see text] particles travel through tissue with energies greater than 219 keV, CR occurs. Tissues possess a spectral optical window of 600 to 1100 nm. The CR within this range can be useful for quantitative preclinical studies using optical imaging and for the in-vivo evaluation of [Formula: see text]-radiopharmaceuticals ([Formula: see text]-particle emitters). The objective of our research was to determine the experimental emission light spectrum of [Formula: see text]-CR and evaluate its transmission properties in tissue as well as the feasibility to applying CR imaging in the preclinical studies of [Formula: see text]-radiopharmaceuticals. The theoretical and experimental characterizations of the emission and transmission spectra of [Formula: see text]-CR in tissue, in the vis-NIR region (350 to 900 nm), were performed using Monte Carlo simulation and UV-vis spectroscopy. Mice [Formula: see text]-CR images were acquired using a charge-coupled detector camera and were quantitatively analyzed. The results demonstrated good agreement between the theoretical and the experimental [Formula: see text]-CR emission spectra. Preclinical CR imaging demonstrated that the biokinetics of [Formula: see text]-radiopharmaceuticals in the main organs of mice can be acquired.