Molecular Imaging and Theranostics Laboratory, Baker Heart and Diabetes Institute, 75 Commercial Road, Melbourne, VIC, 3004, Australia.
Baker Department of Cardiometabolic Health, University of Melbourne, Parkville, VIC, 3010, Australia.
Small Methods. 2024 Oct;8(10):e2400348. doi: 10.1002/smtd.202400348. Epub 2024 Aug 1.
Utilizing cell membranes from diverse cell types for biointerfacing has demonstrated significant advantages in enhancing colloidal stability and incorporating biological properties, tailored specifically for various biomedical applications. However, the structures of these materials, particularly emulsions interfaced with red blood cell (RBC) or platelet (PLT) membranes, remain an underexplored area. This study systematically employs small- and ultra-small-angle neutron scattering (SANS and USANS) with contrast variation to investigate the structure of emulsions containing perfluorohexane within RBC (RBC/PFH) and PLT membranes (PLT/PFH). The findings reveal that the scattering length density of RBC and PLT membranes is 1.5 × 10 Å, similar to 30% (w/w) deuterium oxide. Using this solvent as a cell membrane-matching medium, estimated droplet diameters are 770 nm (RBC/PFH) and 1.5 µm (PLT/PFH), based on polydispersed sphere model fitting. Intriguingly, calculated patterns and invariant analysis reveal native droplet architectures featuring entirely liquid PFH cores, differing significantly from the observed bubble-droplet core system in electron microscopy. This highlights the advantage of SANS and USANS in differentiating genuine colloidal structures in complex dispersions. In summary, this work underscores the pivotal role of SANS and USANS in characterizing biointerfaced colloids and in uncovering novel colloidal structures with significant potential for biomedical applications and clinical translation.
利用来自不同细胞类型的细胞膜进行生物界面工程已被证明在增强胶体稳定性和纳入生物特性方面具有显著优势，这些特性是针对各种生物医学应用专门定制的。然而，这些材料的结构，特别是与红细胞（RBC）或血小板（PLT）膜相互作用的乳液的结构，仍然是一个未得到充分探索的领域。本研究系统地采用小角和超小角中子散射（SANS 和 USANS）与对比变化来研究含有全氟己烷的乳液在 RBC（RBC/PFH）和 PLT 膜（PLT/PFH）中的结构。研究结果表明，RBC 和 PLT 膜的散射长度密度为 1.5×10 Å，类似于 30%（w/w）重水。使用这种溶剂作为细胞膜匹配介质，根据多分散球体模型拟合，估计的液滴直径分别为 770nm（RBC/PFH）和 1.5µm（PLT/PFH）。有趣的是，计算模式和不变量分析揭示了具有全液态 PFH 核的天然液滴结构，这与电子显微镜中观察到的气泡-液滴核系统有很大的不同。这突出了 SANS 和 USANS 在区分复杂分散体中真实胶体结构方面的优势。总之，这项工作强调了 SANS 和 USANS 在表征生物界面胶体以及揭示具有重要生物医学应用和临床转化潜力的新型胶体结构方面的关键作用。
