In vivo biodistribution of edelfosine-loaded lipid nanoparticles radiolabeled with Technetium-99 m: Comparison of administration routes in mice

Edelfosine (ET) is a potent antitumor agent but causes severe side effects that have limited its use in clinical practice. For this reason, nanoencapsulation in lipid nanoparticles (LNs) is advantageous as it protects from ET side-effects. Interestingly, previous studies showed the efficacy of LNs containing ET in various types of tumor. In this paper, biodistribution studies of nanoencapsulated ET, administered by three routes (oral, intravenous (IV) and intraperitoneal (IP)), were tested in order to select the optimal route of administration. To do this, ET-LNs were labeled with Technetium-99 m (Tc-99m) and administered by the oral, IV and IP route in mice. IV administration of the radiolabeled LNs led to fast elimination from the blood circulation and increased accumulation in reticulo-endothelial (RES) organs, while their oral administration could not provide any evidence on their biodistribution since large radiocomplexes were formed in the presence of gastrointestinal fluids. However, when the LNs were administered by the IP route they could access the systemic circulation and provided more constant blood ET-LN levels compared to the IV route. These findings suggest that the IP route can be used to sustain the level of drug in the blood and avoid accumulation in RES organs.

Automated summary

Nanoencapsulated Edelfosine is effective in various types of tumors, and biodistribution studies revealed that the intraperitoneal route is optimal for sustaining consistent blood levels and avoiding accumulation in RES organs.