Fig. 1. SEM micrographs of the synthesized (a) Cit-SP-NCs (ST), (b) Lys-SP-NCs (ST), (c) Cit-SP-NCs (MW), (d) Lys-SP-NCs (MW). Scale bars indicate 500 nm (in white). In the insets, TEM micrographs of single SP-NCs for the primary particle size estimation. Scale bars in the insets indicate 100 nm (in red).