Fig. 1

TEM images of three generations of GFP-ʟ-arginine modified nanoparticles and core particles of GFP(NaHCO₃) modified nanoparticles. In a, c and d, the three generations of GFP(ʟ-arginine) are shown: C_F core particles (a, d_TEM = 15.5 ± 1.1 nm); C_FS_1F nanoparticles after the first regrowth step (core + shell 1) (c, d_TEM = 23.5 ± 2.0 nm) and C_FS_1FS_2F after the second regrowth step (core + shell 1 + shell 2) (d, d_TEM = 35.3 ± 2.0 nm). In b, the GFP(NaHCO₃)-labelled core nanoparticles (d_TEM = 15.2 ± 1.2 nm) are shown