title: Magnetic nanoparticles encapsulated into biodegradable microparticles steered with an upgraded magnetic resonance imaging system for tumor chemoembolization.
abstract: In this work, therapeutic magnetic micro carriers (TMMC) guided in real time by a magnetic resonance imaging (MRI) system are proposed as a mean to improve drug delivery to tumor sites. MRI steering constraints and physiological parameters for the chemoembolization of liver tumors were taken into account to design magnetic iron-cobalt nanoparticles encapsulated into biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) microparticles with the appropriate saturation magnetization (M(s)). FeCo nanoparticles displayed a diameter of 182nm and an M(s) of 209 emicrog(-1). They were coated with a multilayered graphite shell to minimize the reduction of M(s) during the encapsulation steps. FeCo-PLGA microparticles, with a mean diameter of 58 microm and an M(s) of 61emicrog(-1), were steered in a phantom mimicking the hepatic artery and its bifurcation, with a flow in the same order of magnitude as that of the hepatic artery flow. The steering efficiency, defined as the amount of FeCo-PLGA microparticles in the targeted bifurcation channel divided by the total amount of FeCo-PLGA microparticles injected, reached 86%. The data presented in this paper confirms the feasibility of the steering of these TMMC.
authors.affiliation: NanoRobotics Laboratory, Canada Research Chair in Micro/Nanosystem Development, Fabrication and Validation, Department of Computer and Software Engineering and Institute of Biomedical Engineering, Ecole Polytechnique de Montreal (EPM), C.P. 6079, Succursale Centre-ville, Montréal, Québec H3C 3A7, Canada.
authors.forename: Pierre
authors.initials: P
authors.lastname: Pouponneau
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Leroux
authors.forename: Sylvain
authors.initials: S
authors.lastname: Martel
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry*; D016461:Chemoembolization, Therapeutic / Q000379:methods*; D005290:Ferric Compounds / Q000737:chemistry; D006801:Humans; D019344:Lactic Acid / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D009369:Neoplasms / Q000628:therapy*; D011100:Polyglycolic Acid / Q000737:chemistry; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer
chemical_list: D001672:Biocompatible Materials; D005290:Ferric Compounds; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid