One drop of the suspension was diluted in deionised water (2 mL). DLS measurements of PISA assemblies were performed on a Zetasizer Nano ZSP (Malvern Instruments, UK) at 25 °C, 173°. Stock solutions were diluted 1:1000 in PBS in a cuvette, with a final volume of 1 mL, measured during 11 runs, repeated three times. Alexa 405-tagged SIO2 NPs were instead measured according to the same protocol, on a Zetasizer Nano ZS90, at 25°C and 90°. Because of the large size of the polymersomes, only the smaller spherical morphologies were analysed by DLS.