Dynamic light scattering (DLS) measurements were performed at room temperature with an equipment consisting of a goniometer system (ALV GmbH, Langen, Germany), a diode-pumped solid-state laser light source (Melles Griot, IDEX corp., Lake Forest, IL, USA; 58-BLS-301, 457 nm, 150 mW), and a light detector (Hamamatsu, Japan; H7155 PMT module). The evaluation software yielded the autocorrelation function of scattered light intensity, which was further analyzed by the maximum entropy method, from where the different contributions of this function were determined. The radius of the particles was calculated using sphere approximation.36 (link)For nanoparticle tracking analysis (NTA), samples were resuspended in 1 ml of PBS to reach appropriate particle concentration range for the measurement. Particle size distribution and concentration were analyzed on ZetaView PMX120 instrument (Particle Metrix, Inning am Ammersee, Germany). For each measurement, 11 cell positions were scanned at 25°C (in 2 cycles) with the following camera settings: shutter speed—100, sensitivity—75, frame rate—7.5, video quality—medium (30 frames). The videos were analyzed by the ZetaView Analyze software 8.05.10 with a minimum area of 5, maximum area of 1,000, and a minimum brightness of 20.