Fig. 4

Dispersion of van-SiO₂-MNPs and van-PDA-MNPs in PBS (a) and blood (b). The particle size distribution of the MNPs was analysed using Zetasizer. Two hundred microliters of each type of MNP were added to PBS or blood and incubated at 37 °C for 30 min. MNPs were then separated using a permanent magnet and washed with PBS, and the size distribution of van-SiO₂-MNPs (c) and van-PDA-MNPs (d) was analysed