Results are displayed in Fig. (for BSA-Ag NCs) and in Fig. (for Lysozyme- Au NCs). As for gold clusters, the average number of silver atoms observed on BSA strongly depend on the matrix (Fig. ). Moreover, reduced average number of Ag atoms on the protein also correlates with an increase of the signal of bare BSA. However, in the case of silver the highest number of Ag atoms is observed using SA (17 Ag atoms), while CHCA and DHB lead to the observation of significantly smaller species (9-10 Ag atoms).