The physicochemical properties of drug carriers are closely associated with their biological properties, and their detailed analysis is essential for the development of the field of drug delivery systems (DDSs). Synchrotron small-angle X-ray scattering (SAXS) provides accurate nanoscale structural information about drug carriers in solution. This review introduces the structural analysis of three recent types of drug carriers, polyethylene glycol-modified liposomes (PEG-liposomes), cationic liposomes, and microemulsions. First, the quantitative evaluation of PEG chains on the surface of a liposome with a contrast variation technique in SAXS was described. Second, we introduced the localization analysis of glutathione molecules in cationic liposomes with SAXS and showed that the size of the inner phase of the liposome had the greatest effect on the loading amount of glutathione rather than the adsorption of glutathione on the surface of the cationic liposomes. The final section covered microemulsions containing deep eutectic solvents in the inner phase of transdermal DDSs. The structure, drug loading amount, and skin penetration amount of the microemulsion were evaluated.

药物载体的理化性质与其生物学性质密切相关，对其进行详细分析对于药物递送系统（DDSs）领域的发展至关重要。同步加速器小角 X 射线散射 (SAXS) 提供有关溶液中药物载体的准确纳米级结构信息。本综述介绍了最近三种药物载体的结构分析，即聚乙二醇修饰脂质体（PEG-脂质体）、阳离子脂质体和微乳剂。首先，描述了在 SAXS 中使用对比度变化技术对脂质体表面 PEG 链的定量评估。第二，我们用 SAXS 介绍了阳离子脂质体中谷胱甘肽分子的定位分析，结果表明脂质体内相的大小对谷胱甘肽的负载量影响最大，而不是谷胱甘肽在阳离子脂质体表面的吸附。最后一部分介绍了在经皮 DDS 的内相中含有深共熔溶剂的微乳液。评价微乳的结构、载药量和皮肤渗透量。