Figure 6.

Example of a mismatch between fluorescence and gold coupling to proteins of interest. Epidermal growth factor coupled to Alexa488 and 10 nm gold particles internalised into HeLa cells shows bright fluorescence but only one gold particle at the region of interest. Transferrin coupled to Alexa488 and 5 nm gold particles, however, shows a lower fluorescence signal but numerous gold particles. Quenching of the fluorophore and coupling efficiency may play a role in this mismatch. See also [14].