The rapid development of nanotechnology has led to an increase in the number and variety of engineered nanomaterials in the environment. Gold nanoparticles (AuNPs) are an example of a commonly studied nanomaterial whose highly tailorable properties have generated significant interest through a wide range of research fields. In the present work, we characterise the AuNP-lipid membrane interaction by coupling qualitative data with quantitative measurements of the enthalpy change of interaction. We investigate the interactions between citrate-stabilised AuNPs ranging from 5 to 60 nm in diameter and large unilamellar vesicles acting as a model membrane system. Our results reveal the existence of two critical AuNP diameters which determine their fate when in contact with a lipid membrane. The results provide new insights into the size dependent interaction between AuNPs and lipid bilayers which is of direct relevance to nanotoxicology and to the design of NP vectors.

纳米技术的快速发展导致环境中工程纳米材料的数量和种类不断增加。金纳米粒子 (AuNP) 是一种常被研究的纳米材料，其高度可定制的特性在广泛的研究领域引起了极大的兴趣。在目前的工作中，我们通过将定性数据与相互作用的焓变的定量测量相结合来表征 AuNP-脂质膜相互作用。我们研究了直径范围为 5 至 60 nm 的柠檬酸盐稳定的 AuNP 与充当模型膜系统的大单层囊泡之间的相互作用。我们的结果揭示了两个临界 AuNP 直径的存在，这决定了它们在与脂质膜接触时的命运。