The present article describes the preparation of beta emitter lutetium-177-lebeled zirconia colloid and its preliminary physico-chemical and biological evaluation of suitability for local radionuclide therapy.
The new 177Lu-labeled therapeutic radiopharmaceutical candidate was based on the synthesis mode of a previously described zirconia nanoparticle system. Morphology and size of developed radiopharmaceutical compound were evaluated through scanning electron microscope and dynamic light scattering methods. The radiocolloid had a 1.7 micrometer mean diameter and showed suitable radiolabeling and colloid size in vitro stability at RT and during blood sera stability test. After the in vitro characterizations, the product was investigated in the course of the treatment of a spontaneously diseased dog veterinary patient’s hock joint completed with SPECT imaging follow-up measurements and a dual-isotope SPECT imaging tests with conventional 99mTc-MDP bone scintigraphy. In the treated dog any clinical side effects or signs of histopatological alterations of the joints could not be observed during the treatment. SPECT follow-up studies unequivocally showed appropriately high localization of the 177Lu-labeled colloid in hock joint and detectable but negligible radiocolloid leakages in the nearest lymph node, respectively