Chelating Complex Micelles for Delivering Cytoprotectant Amifostine and its Application in Radiation Protection

A new nano-size drug carrier was proposed to overcome the shortcomings of conventional drug delivery systems. Amifsotine, a hydrophilic and extremely short half-life cytoprotective agent, was loaded based on chelating complex micelles (CCM) in order to provide the protection from radiation exposure. The preparation of amifostine-loaded CCM (CCM-Ami) was simply mixing ferrous chloride, poly(ethylene glycol)-block-poly (glutamic acid) (PEG-b-PGA) and amifostine in an aqueous solution without using any organic solvent. The resulting CCM-Ami monodispersed with a mean particle size 25 nm and showed a slow release behavior as compared to amifostine. Furthermore, CCM-Ami pretreatment improved survival rates and median survival in C57BL/6 mice than did treatment with a corresponding dose of amifostine. These results point to a potential use of CCM as a novel drug carrier. Drug molecules that may act as ligands can be considered delivering by this platform technology.