Fig. 3

Transmission electron microscopy (TEM) photograph of goldnanoparticle (bar 50 nm). Only GNP (a) and GNP with protein core (b). Arrow indicates protein core around the GNP. Actual size of gold nanoparticle measured by atomic force microscope. Where only GNP showed 5–25 nm (c), GNP-NKCT1 showed 40–220 nm (d)