Preparation, characterization and magnetic resonance's response characteristics of folate-functionilazed superparamagnetic iron oxide and sorafenib-loaded polymeric micelles

Abstract

Objective To prepare and analyze the physical characteristics of folate-functionalized superparamagnetic iron oxide (SPIO)-sorafenib-micelles (targeted micelles) and folate-free sorafenib and SPION-loaded micelles (non-targeted micelles) and to observe the feasibility of minitoring the targeting therapeutic effect with magnetic resonance imaging (MRI).Methods SPION were loaded into polymeric micelles.The targeted nanocarrier was synthesized by functionalizing the micelles with folate.Folate-free sorafenib and SPION-loaded micelles were used as controls.The physical characteristics of these nano-micelles including particle diameter,magnetic character,sorafenib or SPIO-loading contents,etc,were determined.MRI was performed to detect the signal intensity changes of cells after incubation with polymeric micelles at a clinical 1.5 T scanner.Results The targeted micelles and non-targeted micelles were prepared successfully,and the physical characteristics of these nano-micelles were determined.Transmission electron microscope (TEM) showed that the micelles were of nano dimension.The magnetization curves of the micelles demonstrated that the SPIO-micelles had superparamagnetism.Sorafenib and SPIO-loaded contents were high.The T2 signal intensity on MRI of cells treated with targeted micelles was decreased significantly with the increase of the concentration of sorafenib in cell culture medium,while no obvious signal was decreased for cells treated with the non-targeted micelles.Conclusion Folate-functionilazed SPIO and sorafenib-loaded polymeric micelles and folate-free sorafenib and SPION-loaded micelles which have superparamagnetism were prepared successfully.The targeted inhibitory events of the micelles to HepG2 cells can be monitored using a clinical MRI unit. Key words: Superparamagnetic iron oxide nanoparticles ; Sorafenib; Folic acid; Magnetic resonance imaging; Nano-micelles