Unruh Tobias, Götz Klaus, Vogel Carola, Fröhlich Erik, Scheurer Andreas, Porcar Lionel, Steiniger Frank
Institute for Crystallography and Structural Physics, Physics Department, Friedrich-Alexander-Universität Erlangen-Nürnberg, Staudtstraße 3, 91058 Erlangen, Germany.
Interdisciplinary Center for Nanostructured Films (IZNF) and Center for Nanoanalysis and Electron Microscopy (CENEM), Cauerstraße 3, 91058 Erlangen, Germany.
ACS Nano. 2024 Apr 2;18(13):9746-9764. doi: 10.1021/acsnano.4c02610. Epub 2024 Mar 21.
Lipid nanoparticles (LNPs) produced by antisolvent precipitation (ASP) are used in formulations for mRNA drug delivery. The mesoscopic structure of such complex multicomponent and polydisperse nanoparticulate systems is most relevant for their drug delivery properties, medical efficiency, shelf life, and possible side effects. However, the knowledge on the structural details of such formulations is very limited. Essentially no such information is publicly available for pharmaceutical dispersions approved by numerous medicine agencies for the use in humans and loaded with mRNA encoding a mimic of the spike protein of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) as, e.g., the Comirnaty formulation (BioNTech/Pfizer). Here, we present a simple preparation method to mimic the Comirnaty drug-free LNPs including a comparison of their structural properties with those of Comirnaty. Strong evidence for the liquid state of the LNPs in both systems is found in contrast to the designation of the LNPs as solid lipid nanoparticles by BioNTech. An exceptionally detailed and reliable structural model for the LNPs i.a. revealing their unexpected narrow size distribution will be presented based on a combined small-angle X-ray scattering and photon correlation spectroscopy (SAXS/PCS) evaluation method. The results from this experimental approach are supported by light microscopy, H NMR spectroscopy, Raman spectroscopy, cryogenic electron microscopy (cryoTEM), and simultaneous SAXS/SANS studies. The presented results do not provide direct insights on particle formation or dispersion stability but should contribute significantly to better understanding the LNP drug delivery process, enhancing their medical benefit, and reducing side effects.
通过反溶剂沉淀法（ASP）制备的脂质纳米颗粒（LNPs）用于mRNA药物递送制剂中。这种复杂的多组分且多分散的纳米颗粒系统的介观结构与其药物递送特性、医疗效果、保质期以及可能的副作用最为相关。然而，关于此类制剂结构细节的知识非常有限。基本上，对于众多医药机构批准用于人类且负载编码严重急性呼吸综合征冠状病毒2型（SARS-CoV-2）刺突蛋白模拟物的mRNA的药物分散体，例如Comirnaty制剂（BioNTech/辉瑞），没有此类公开信息。在此，我们提出一种简单的制备方法来模拟不含药物的Comirnaty LNPs，并将其结构特性与Comirnaty的结构特性进行比较。与BioNTech将LNPs指定为固体脂质纳米颗粒相反，我们发现这两种系统中的LNPs均处于液态。基于小角X射线散射和光子相关光谱（SAXS/PCS）联合评估方法，将给出一个异常详细且可靠的LNPs结构模型，该模型揭示了它们出人意料的窄尺寸分布。光学显微镜、1H核磁共振光谱、拉曼光谱、低温电子显微镜（cryoTEM）以及同步SAXS/SANS研究均支持了该实验方法的结果。所呈现的结果并未提供关于颗粒形成或分散稳定性的直接见解，但应有助于更好地理解LNP药物递送过程、提高其医疗效益并减少副作用。
