We have improved the sample preparation process by hydrophilically treating the copper mesh, thus providing a hydrophilic coating. With this treatment, the samples are more easily and uniformly adsorbed into the carbon membrane. We took transmission electron microscopy (TEM) images of exosomes and liposomes. The exosomes presented a typical cup-like morphology (Figure 2A),and spherical liposomes were uniformly distributed (Figure S2).Translated with www.DeepL.com/Translator (free version)