Nanophox 90 250 5

PCCS (Photon cross correlation spectroscopy) was used to study changes in size distribution of the particles, agglomeration and concentration (possible reduction due to sedimentation) over time in the cell medium. Particle suspensions of 1 mg/mL medium were prepared by ultrasonication for 2 × 10 min alternated by 10 s vortexing at 37 °C. The samples were prepared in disposable single sealed cuvettes, LOTG17501P (Eppendorf AG, Hamburg, Germany) at a concentration of 0.1 mg/mL. The samples were stored at 37 °C and measured in triplicates after 0, 2 and 24 h using the NANOPHOX 90–250 V (Sympatec GmbH, Claustahl-Zellerfeld, Germany) instrument. Windox 5, the PCCS software (version 10, SympatecGmbH, Claustahl-Zellerfeld, Germany), was used to fit the size distribution data for each measurement. Measurements of standard latex particles (100 nm) and non-particle containing media were performed to ensure high quality data. The samples were measured after 24 h. Measurements were performed on the metal and metal oxide NPs as well as the QDs.
Particle size measurements of the Au, Ag and Pt NPs were determined using NTA (Nanoparticle Tracking Analysis) as described in Lebedova et al. [23 (link)].

Photon cross correlation spectroscopy (PCCS) was used to investigate size distribution and sedimentation of the NPs, prepared according to the described protocol and diluted to 20 µg/mL in a cell culture medium (with or without serum). The samples were prepared in disposable single sealed cuvettes, LOTG17501P (Eppendorf AB), and measured in triplicate immediately after preparation, as well as after 24 h using the NANOPHOX 90-250 V (Sympatec, Clausthal Germany) instrument. The software Windox (Clausthal, v.5) was used to obtain the size distribution data for each measurement. Measurements of standard latex particles (100 nm) were performed to ensure accurate measurements of particle size.