NP size, polydispersity, and superficial
charge are measured by dynamic light scattering (DLS, Zetasizer Nano
ZS, Malvern U.K.). Typically, 1 mL of the diluted sample is put in
12 mm square glass cuvettes for 90° sizing (Optical Cuvette,
Sarstedt) and measured at least in triplicate. ζ potential measurements
are performed at room temperature on a Zetasizer Nano ZS (Malvern,
U.K.), fitted with a high-concentration ζ potential cell. Nanoparticle
morphology is assessed by scanning and transmission electron microscopy,
SEM and TEM, respectively. For SEM observations (Carl Zeiss Ultraplus
Field Emission), 100 μL of purified samples are dropped on a
polycarbonate isopore membrane filter (cutoff 0.05 μm) under
vacuum ultrafiltration and let dry overnight. Before the observation,
5–7 nm of Au is deposited on the sample. For cryo-TEM observation
of EVs (Cryo-TEM TECNAI by FEI), 5 μL of the purified sample
is dropped on a Formvar/Carbon 200 mesh grid (Agar scientific) and
observed at an 80 kV accelerating voltage. The concentration of cHANPs
and EVs is quantified by nanoparticle tracking analysis NTA (Nanosight
NS300, Malvern Instruments Ltd., U.K.). Both samples are observed
at a dilution of 1:100, at 25 °C for 300 s with a manual shutter
and gain adjustment. Results are analyzed with NP Tracking Analysis
software.
charge are measured by dynamic light scattering (DLS, Zetasizer Nano
ZS, Malvern U.K.). Typically, 1 mL of the diluted sample is put in
12 mm square glass cuvettes for 90° sizing (Optical Cuvette,
Sarstedt) and measured at least in triplicate. ζ potential measurements
are performed at room temperature on a Zetasizer Nano ZS (Malvern,
U.K.), fitted with a high-concentration ζ potential cell. Nanoparticle
morphology is assessed by scanning and transmission electron microscopy,
SEM and TEM, respectively. For SEM observations (Carl Zeiss Ultraplus
Field Emission), 100 μL of purified samples are dropped on a
polycarbonate isopore membrane filter (cutoff 0.05 μm) under
vacuum ultrafiltration and let dry overnight. Before the observation,
5–7 nm of Au is deposited on the sample. For cryo-TEM observation
of EVs (Cryo-TEM TECNAI by FEI), 5 μL of the purified sample
is dropped on a Formvar/Carbon 200 mesh grid (Agar scientific) and
observed at an 80 kV accelerating voltage. The concentration of cHANPs
and EVs is quantified by nanoparticle tracking analysis NTA (Nanosight
NS300, Malvern Instruments Ltd., U.K.). Both samples are observed
at a dilution of 1:100, at 25 °C for 300 s with a manual shutter
and gain adjustment. Results are analyzed with NP Tracking Analysis
software.