German Federal Institute for Risk Assessment , Department of Food Safety, Max-Dohrn-Straße 8-10, 10589 Berlin, Germany.
Bundesanstalt für Materialforschung und -prüfung (BAM) , Unter den Eichen 87, 12205 Berlin, Germany.
Langmuir. 2017 Oct 10;33(40):10726-10735. doi: 10.1021/acs.langmuir.7b02729. Epub 2017 Sep 26.
Aluminum has gathered toxicological attention based on relevant human exposure and its suspected hazardous potential. Nanoparticles from food supplements or food contact materials may reach the human gastrointestinal tract. Here, we monitored the physicochemical fate of aluminum-containing nanoparticles and aluminum ions when passaging an in vitro model of the human gastrointestinal tract. Small-angle X-ray scattering (SAXS), transmission electron microscopy (TEM), ion beam microscopy (IBM), secondary ion beam mass spectrometry (TOF-SIMS), and inductively coupled plasma mass spectrometry (ICP-MS) in the single-particle mode were employed to characterize two aluminum-containing nanomaterials with different particle core materials (Al, γAlO) and soluble AlCl. Particle size and shape remained unchanged in saliva, whereas strong agglomeration of both aluminum nanoparticle species was observed at low pH in gastric fluid together with an increased ion release. The levels of free aluminum ions decreased in intestinal fluid and the particles deagglomerated, thus liberating primary particles again. Dissolution of nanoparticles was limited and substantial changes of their shape and size were not detected. The amounts of particle-associated phosphorus, chlorine, potassium, and calcium increased in intestinal fluid, as compared to nanoparticles in standard dispersion. Interestingly, nanoparticles were found in the intestinal fluid after addition of ionic aluminum. We provide a comprehensive characterization of the fate of aluminum nanoparticles in simulated gastrointestinal fluids, demonstrating that orally ingested nanoparticles probably reach the intestinal epithelium. The balance between dissolution and de novo complex formation should be considered when evaluating nanotoxicological experiments.
铝因其相关的人类暴露和潜在的危害性而引起了毒理学关注。来自食品补充剂或食品接触材料的纳米颗粒可能会进入人体胃肠道。在这里，我们监测了含有铝的纳米颗粒和铝离子在通过人体胃肠道体外模型时的物理化学命运。采用小角 X 射线散射（SAXS）、透射电子显微镜（TEM）、离子束显微镜（IBM）、二次离子质谱（TOF-SIMS）和电感耦合等离子体质谱（ICP-MS）的单颗粒模式对两种具有不同颗粒核材料（Al、γAlO）和可溶性 AlCl 的含铝纳米材料进行了表征。在唾液中，颗粒的大小和形状保持不变，而在胃液的低 pH 值下，两种铝纳米颗粒都发生了强烈的团聚，同时伴随着离子释放的增加。在肠液中，游离铝离子的水平下降，颗粒解团聚，再次释放出初级颗粒。纳米颗粒的溶解受到限制，其形状和大小没有明显变化。与标准分散体中的纳米颗粒相比，肠液中颗粒相关的磷、氯、钾和钙的含量增加。有趣的是，在添加离子铝后，在肠液中发现了纳米颗粒。我们对铝纳米颗粒在模拟胃肠道液中的命运进行了全面的表征，证明口服摄入的纳米颗粒可能到达肠上皮细胞。在评估纳米毒理学实验时，应考虑溶解和新形成复合物之间的平衡。
