Guven Zekiye P, Silva Paulo H Jacob, Luo Zhi, Cendrowska Urszula B, Gasbarri Matteo, Jones Samuel T, Stellacci Francesco
Institute of Materials, École Polytechnique Fédérale de Lausanne.
Institute of Materials, École Polytechnique Fédérale de Lausanne; School of Materials, University of Manchester.
J Vis Exp. 2019 Jul 2(149). doi: 10.3791/58872.
Gold nanoparticles covered with a mixture of 1-octanethiol (OT) and 11-mercapto-1-undecane sulfonic acid (MUS) have been extensively studied because of their interactions with cell membranes, lipid bilayers, and viruses. The hydrophilic ligands make these particles colloidally stable in aqueous solutions and the combination with hydrophobic ligands creates an amphiphilic particle that can be loaded with hydrophobic drugs, fuse with the lipid membranes, and resist nonspecific protein adsorption. Many of these properties depend on nanoparticle size and the composition of the ligand shell. It is, therefore, crucial to have a reproducible synthetic method and reliable characterization techniques that allow the determination of nanoparticle properties and the ligand shell composition. Here, a one-phase chemical reduction, followed by a thorough purification to synthesize these nanoparticles with diameters below 5 nm, is presented. The ratio between the two ligands on the surface of the nanoparticle can be tuned through their stoichiometric ratio used during synthesis. We demonstrate how various routine techniques, such as transmission electron microscopy (TEM), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA), and ultraviolet-visible (UV-Vis) spectrometry, are combined to comprehensively characterize the physicochemical parameters of the nanoparticles.
覆盖有1-辛硫醇（OT）和11-巯基-1-十一烷磺酸（MUS）混合物的金纳米颗粒因其与细胞膜、脂质双层和病毒的相互作用而受到广泛研究。亲水性配体使这些颗粒在水溶液中具有胶体稳定性，与疏水性配体的结合产生了一种两亲性颗粒，这种颗粒可以负载疏水性药物，与脂质膜融合，并抵抗非特异性蛋白质吸附。这些特性中的许多都取决于纳米颗粒的大小和配体壳层的组成。因此，拥有一种可重复的合成方法和可靠的表征技术至关重要，这些技术能够确定纳米颗粒的性质和配体壳层的组成。在此，介绍一种单相化学还原方法，随后进行彻底纯化，以合成直径小于5 nm的这些纳米颗粒。纳米颗粒表面两种配体之间的比例可以通过合成过程中使用的化学计量比进行调节。我们展示了如何将各种常规技术，如透射电子显微镜（TEM）、核磁共振（NMR）、热重分析（TGA）和紫外可见（UV-Vis）光谱法结合起来，以全面表征纳米颗粒的物理化学参数。
