title: Ligand-Free Synthesis of Tunable Size Ln:BaGdF₅ (Ln = Eu³⁺ and Nd³⁺) Nanoparticles: Luminescence, Magnetic Properties, and Biocompatibility.
abstract: Bifunctional and highly uniform Ln:BaGdF5 (Ln = Eu(3+) and Nd(3+)) nanoparticles have been successfully synthesized using a solvothermal method consisting of the aging at 120 °C of a glycerol solution containing the corresponding Lanthanide acetylacetonates and butylmethylimidazolium tetrafluoroborate. The absence of any surfactant in the synthesis process rendered hydrophilic nanospheres (with tunable diameter from 45 nm 85 nm, depending on the cations concentration of the starting solution) which are suitable for bioapplications. The particles are bifunctional because they showed both optical and magnetic properties due to the presence of the optically active lanthanides (Eu(3+) in the visible and Nd(3+) in the NIR regions of the electromagnetic spectrum) and the paramagnetic gadolinium ion, respectively. The luminescence decay curves of the nanospheres doped with different amounts of Eu(3+) and Nd(3+) have been recorded in order to determine the optimum dopant concentration in each case, which turned out to be 5% Eu(3+) and 0.5% Nd(3+). Likewise, proton relaxation times were measured at 1.5 T in water suspensions of the optimum particles found in the luminescence study. The values obtained suggested that both kinds of particles could be used as positive contrast agents for MRI. Finally, it was demonstrated that both the 5% Eu(3+) and 0.5% Nd(3+)-doped BaGdF5 nanospheres showed negligible cytotoxicity for VERO cells for concentrations up to 0.25 mg mL(-1).
authors.affiliation: Instituto de Ciencia de Materiales de Sevilla (CSIC-US) , c/Américo Vespucio, 49, 41092 Seville, Spain.
authors.forename: Ana I
authors.initials: AI
authors.lastname: Becerro
authors.affiliation: Instituto de Ciencia de Materiales de Sevilla (CSIC-US) , c/Américo Vespucio, 49, 41092 Seville, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: González-Mancebo
authors.affiliation: Departamento Física de Materiales, C-04, Universidad Autónoma de Madrid , 28049 Madrid, Spain.
authors.forename: Eugenio
authors.initials: E
authors.lastname: Cantelar
authors.affiliation: Departamento Física de Materiales, C-04, Universidad Autónoma de Madrid , 28049 Madrid, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Cussó
authors.affiliation: Instituto de Nanociencia de Aragón, Universidad de Zaragoza , c/Mariano Esquilor s/n, 50018 Zaragoza, Spain.
authors.forename: Grazyna
authors.initials: G
authors.lastname: Stepien
authors.affiliation: Instituto de Ciencia de Materiales de Aragon, CSIC/University of Zaragoza , C/Pedro Cerbuna, 12, 50009 Zaragoza, Spain.
authors.forename: Jesús M
authors.initials: JM
authors.lastname: de la Fuente
authors.affiliation: Instituto de Ciencia de Materiales de Sevilla (CSIC-US) , c/Américo Vespucio, 49, 41092 Seville, Spain.
authors.forename: Manuel
authors.initials: M
authors.lastname: Ocaña