title: On-command controlled drug release by diels-Alder reaction using Bi-magnetic core/shell nano-carriers.
abstract: A novel bi-functional thermo-responsive system, consisting of core/shell bi-magnetic nanoparticles with furan surface functionality, is bonded with N-(2-Carboxyethyl)maleimide through Diels-Alder reaction. The chemotherapeutics doxorubicin is attached onto the surface, with a high loading efficiency of 92%. This system with high responsiveness to a high frequency external alternating magnetic field shows a very good therapeutic efficiency in hyperthermia and drug release at relatively low temperatures (50°C). Polyhedron-shaped bi-magnetic nanoparticles (Zn0.4Co0.6Fe2O4@Zn0.4Mn0.6Fe2O4) exhibit a significant increase of the specific energy absorption rate up to 455W/g compared with the core nanoparticles (200W/g). Real-time florescence spectroscopy studies demonstrate rapid release of doxorubicin up to 50% in 5min and up to 92% after 15min upon exposure to high frequency external alternating magnetic field. The stability is evaluated for 8 weeks in phosphate buffer saline with a doxorubicin payload of 85%. In vitro studies using standard MTT cell assays with HeLa and Hep G2 lines prove an excellent biocompatibility with about 90% of cell viability after 24h of treatment within the highest concentration of functionalized magnetic nanoparticles (200μg/mL). The results indicate a controlled drug release mediated by thermo-responsive switching under applied alternating magnetic field.
authors.affiliation: Department of Physical Chemistry, Saarland University, Saarbrücken 66123, Germany.
authors.forename: Mohaned
authors.initials: M
authors.lastname: Hammad
authors.affiliation: Department of Physical Chemistry, Saarland University, Saarbrücken 66123, Germany; Department of Physics, "Alexandru Ioan Cuza" University of Iasi, Iasi 700506, Romania.
authors.forename: Valentin
authors.initials: V
authors.lastname: Nica
authors.affiliation: Department of Physical Chemistry, Saarland University, Saarbrücken 66123, Germany. Electronic address: r.hempelmann@mx.uni-saarland.de.
authors.forename: Rolf
authors.initials: R
authors.lastname: Hempelmann
mesh_terms: D001672:Biocompatible Materials / Q000737:chemistry; D061565:Cycloaddition Reaction; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000138:chemical synthesis* / Q000737:chemistry; D004317:Doxorubicin / Q000008:administration & dosage* / Q000737:chemistry*; D016503:Drug Delivery Systems; D065546:Drug Liberation; D006367:HeLa Cells; D056945:Hep G2 Cells; D006358:Hot Temperature; D006801:Humans; D060526:Magnetic Fields; D053758:Nanoparticles / Q000737:chemistry; D010710:Phosphates / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D017550:Spectroscopy, Fourier Transform Infrared; D014961:X-Ray Diffraction
chemical_list: D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D010710:Phosphates; D004317:Doxorubicin
keywords: Bi-magnetic nanoparticles; Controlled release; Core/shell; Diels-Adler; Doxorubicin