Magnetic inductive heating of organs of mouse models treated by copolymer coated Fe3O4 nanoparticles

Biodistribution studies provide basic information to design and perform various applications of superparamagnetic iron oxide magnetic nanoparticles (SPIOs) in biomedicine such as drug delivery, MRI as well as hyperthermia. Recently, several quantitative measurements as well as new imaging methods have been used to characterize the SPIOs distribution in organs and in tissues of animal model. In this report we used the fabricated iron oxide nanoparticles coated with two block copolymers of polystyrene-co-polyacrylic acid (St-co-PAA) and polylactic acid-co-polyethylene glycol (PLA-PEG). The biodistributions were investigated ex-vivo for several organs of both healthy and Sarcoma transplanted Swiss mice. The SPIOs concentrations were verified mainly by magnetic inductive heating (MIH) measurement with a combination with atomic absorption spectroscopy (AAS). The results indicated the density detected highest in liver and lowest in kidney. The SPIOs concentration increased significantly up to 24 h after the injection. The observations by our two methods not only are in agreement with each other but also consistent with the tendency reported by other techniques. Discussion will also concern injection strategy for various aspects of hyperthermia applications.