Fig. 3.

ND stability over time. A,B) ND stability over 1 week at 4 °C. NDs were produced by sonication for a total active time of 60 s at 72 W, with a pulse of 7 s and 30% duty cycle. On the left, the graph shows the diameter of NDs over time. There was no statistical difference (p > 0.05) between diameters measured at different time points. On the right, boxplots showing the polydispersity index of NDs, at the different time points tested. Values obtained after production and after two hours were smaller (p < 0.05) than the other values. C,D) ND stability over 110 min at 37 °C. NDs were sonicated for a total active time of 60 s at 72 W, with a pulse of 7 s and 30% duty cycle. On the left, the graph shows the mean ND diameter and standard deviation over time. There was no statistical difference (p > 0.05) between the different values obtained. On the right, boxplots show the ND PDI and its standard deviation. No statistical difference was found (p > 0.05) between these values. Three different samples were tested for each case (N = 3). E) Bright field microscope images (50x magnification) taken from a sample of NDs stored at 37 °C. Pictures were taken every 10 min, up to 110 min. Some small MBs were present just after production; from 40 min onwards, larger MBs were detected.