González-Mancebo Daniel, Becerro Ana Isabel, Cantelar Eugenio, Cussó Fernando, Briat Arnaud, Boyer Damien, Ocaña Manuel
Instituto de Ciencia de Materiales de Sevilla (CSIC-US), c/Américo Vespucio, 49, 41092 Seville, Spain.
Dalton Trans. 2017 May 23;46(20):6580-6587. doi: 10.1039/c7dt00453b.
Uniform, hydrophilic 50 nm diameter Nd-doped BaLuF nanospheres are synthesized at 120 °C using a singular one-pot method based on the use of ethylene glycol as solvent, in the absence of any additive. The composition and crystal structure of the undoped material are analyzed in detail using ICP and XRD, which reveals a BaF cubic crystal structure that is able to incorporate 70 mol% of Lu ions. This finding contrasts with the reported phase diagram of the system, where the maximum solubility is around 30 mol% Lu. XRD proves as well that the BaLuF structure is able to incorporate Nd ions up to, at least 10 mol%, without altering the uniform particles morphology. The Nd-doped particles exhibit near-infrared luminescence when excited at 810 nm. The maximum emission intensity with the minimum concentration quenching effect is obtained at 1.5% Nd doping level. X-ray computed tomography experiments are carried out on powder samples of the latter composition. The sample significantly absorbs X-ray photons, thus demonstrating that the Nd-doped BaLuF nanospheres are good candidates as contrast agents in computed tomography.
采用单一的一锅法，以乙二醇为溶剂，在无任何添加剂的情况下，于120℃合成了直径为50nm、均匀且亲水性的掺钕BaLuF纳米球。使用电感耦合等离子体质谱（ICP）和X射线衍射（XRD）对未掺杂材料的成分和晶体结构进行了详细分析，结果表明其为BaF立方晶体结构，能够掺入70摩尔%的镥离子。这一发现与报道的该体系相图形成对比，在该相图中，镥的最大溶解度约为30摩尔%。XRD还证明，BaLuF结构能够掺入至少10摩尔%的钕离子，而不会改变均匀颗粒的形态。掺钕颗粒在810nm激发时呈现近红外发光。在1.5%的钕掺杂水平下获得了具有最小浓度猝灭效应的最大发射强度。对后一种成分的粉末样品进行了X射线计算机断层扫描实验。该样品能显著吸收X射线光子，从而表明掺钕BaLuF纳米球是计算机断层扫描中优良的造影剂候选材料。
