Synthesis, radiolabeling, and biodistribution of 99 m-technetium-labeled zif-8 nanoparticles for targeted imaging...

This study investigates the synthesis and radiolabeling of zeolitic imidazolate frameworks (ZIF-8) with the radioisotope technetium-99 m (^99mTc) using a solvothermal method in methanol. The methanolic medium facilitated the formation of nanoparticles with favorable characteristics, including a smaller particle size (198 ± 9.8 nm) and a low polydispersity index (PDI = 0.219 ± 0.011). Radiolabeling efficiency (RE%) and radiochemical purity (RCP%) were optimized by employing SnCl₂ as a reducing agent, resulting in an RE% of 95.2 ± 1.9% and an RCP% of 96.1 ± 1.7% in triplicate (n = 3) at 65 °C. The nanoparticles exhibited high serum stability, retaining 99.05% of RCP% after 24 h, and demonstrated hemocompatibility, with hemolysis rates below 5% across all tested concentrations. In vitro biocompatibility assessments using NIH-3T3 cells indicated cell viability above 70% at concentrations up to 40 μg/mL. Biodistribution studies in rabbits (n = 6) revealed predominant accumulation in the bladder, with radiotracer uptake in the bladder being 6.3, 7.2, and 36.2 times higher than in the liver, kidneys, and heart (p < 0.0001), respectively, suggesting renal clearance. These results underscore the potential of ^99mTc-(ZIF-8) nanoparticles for biomedical applications, particularly in targeted imaging and drug delivery. Future research will focus on improving targeting specificity and enhancing therapeutic efficacy in disease models.

The online version contains supplementary material available at 10.1007/s13205-024-04145-w.