Figure 2.

Histograms showing hydrodynamic size distribution of 5 nm AuNPs at 4, 12, and 24 h time points from top to bottom. Size measurements of AuNP solutions were carried out in the presence of serum proteins at RT and 37 °C and were continuously measured for 24 h. Data shows absolutely no change in hydrodynamic size when measured in serum at RT (4 h, 10 nm; 12 h, 10 nm; 24 h, 10 nm), whereas there was an observable change in the AuNP size when measured in serum (4 h, 19 nm; 12 h, 18 nm; 24 h, 18 nm) as well as a broad size distribution.