Superparamagnetic PLGA–iron oxide microspheres as contrast agents for dual-imaging and the enhancement of the effects of high-intensity focused ultrasound ablation on liver tissue

摘要: Efforts have been made to develop a multifunctional platform that could provide both diagnostic information and therapeutic effect. In this study, superparamagnetic poly(lactic-co-glycolic acid) (PLGA)–iron oxide (uSPIO/PLGA) microspheres were prepared for application in ultrasound (US) magnetic resonance imaging (MRI) the enhancement of efficiency high-intensity focused (HIFU) on liver tissue through an intravenous injection. Highly dispersed, regular spherical negatively charged uSPIO/PLGA fabricated by typical double emulsion method which uSPIO nanoparticles observed integrated into PLGA microspheres. The Fe (iron) concentration was determined using atomic absorption spectrometry. our experiment, showed higher echogenicity than saline US imaging. Furthermore, appeared enhance T2-weighted (T2WI) imaging, with MR signal intensity decreasing increase content. introduced bovine rabbits evaluate HIFU synergistic ablation vitro vivo. After intravascular administration microspheres, ablated HIFU, exposed subjected pathological examination determine its structural variation. Pure (without uSPIO) used as controls. Our results show coagulative necrosis volume degree group significantly greater group. employment composite dual-modality US/MR therapy method.