Bäumler Magdalena, Schwaminger Sebastian P, von der Haar-Leistl Daniela, Schaper Simon J, Müller-Buschbaum Peter, Wagner Friedrich E, Berensmeier Sonja
Bioseparation Engineering Group, Department of Mechanical Engineering, Technical University of Munich Boltzmannstraße 15 85748 Garching Germany
Fraunhofer Institute for Process Engineering and Packaging (IVV), Department of Process Development for Plant Raw Materials Giggenhauser Str. 35 85354 Freising Germany.
RSC Adv. 2021 May 14;11(29):17669-17682. doi: 10.1039/d1ra00050k. eCollection 2021 May 13.
Kidney disease is one of the main non-communicable diseases. Every year millions of people worldwide die from kidney dysfunction. One cause is disturbances in the mineral metabolism, such as abnormally high phosphate concentrations in the blood, medically referred to as hyperphosphatemia. A new active ingredient based on nanoscale iron(oxyhydr)oxide with particle sizes below 3 nm surrounded by an organic coating has been developed for a more effective treatment. The examination of the structural properties of these particles within this study promises to gain further insights into this improved effectiveness. More than half of the active ingredient consists of organic substances, the rest is mostly iron(oxyhydr)oxide. Analyzes by transmission electron microscopy (TEM), small-angle X-ray scattering (SAXS), and dynamic light scattering (DLS) show that the organic molecules act as stabilizers and lead to ultrasmall iron(oxyhydr)oxide cores with a size of 1.0-2.8 nm. The nanoparticles coated with the organic molecules have an average size of 11.7 nm. At 4.2 K, the nanoparticles display a magnetic hyperfine field of 45.5 T in the Mössbauer spectrum, which is unusually low for iron(oxyhydr)oxide. The material is also not ferrimagnetic. Combining these results and taking into account the composition of the nanoparticles, we identify low crystalline ferrihydrite as the most likely phase in the iron(oxyhydr)oxide nuclei. At the same time, we want to emphasize that a final identification of the crystal structure in iron(oxyhydr)oxides can be impeded by ultrasmall particle sizes. In summary, by a combinatorial characterization, we are able to observe extraordinary properties of the ultrasmall nanomaterial, which is the basis for the investigation of the high phosphate-binding efficacy of this active ingredient.
肾脏疾病是主要的非传染性疾病之一。每年全球有数百万人死于肾功能障碍。其中一个原因是矿物质代谢紊乱，比如血液中磷酸盐浓度异常升高，医学上称为高磷血症。人们研发了一种基于纳米级铁（氢）氧化物的新型活性成分，其粒径小于3纳米，并被一层有机涂层包裹，用于更有效的治疗。在本研究中对这些颗粒的结构特性进行检测，有望进一步深入了解这种提高的有效性。超过一半的活性成分由有机物质组成，其余大部分是铁（氢）氧化物。通过透射电子显微镜（TEM）、小角X射线散射（SAXS）和动态光散射（DLS）分析表明，有机分子起到稳定剂的作用，并形成了尺寸为1.0 - 2.8纳米的超小铁（氢）氧化物核。包覆有机分子的纳米颗粒平均尺寸为11.7纳米。在4.2 K时，纳米颗粒在穆斯堡尔谱中显示出45.5 T的磁超精细场，这对于铁（氢）氧化物来说异常低。该材料也不是亚铁磁性的。综合这些结果并考虑到纳米颗粒的组成，我们确定低结晶度的水铁矿是铁（氢）氧化物核中最可能的相。同时，我们想强调的是，超小粒径可能会阻碍对铁（氢）氧化物晶体结构的最终鉴定。总之，通过组合表征，我们能够观察到这种超小纳米材料的非凡特性，这是研究该活性成分高磷酸盐结合效能的基础。
