Surface functionalization of Ag-nanoclusters–silica composite films for biosensing

Ag nanocluster–silica composite films have been obtained by Radio-Frequency (RF) co-sputtering on soda-lime substrates: their characteristic Localized Surface Plasmon Resonance (LSPR) can be employed for sensing applications after grafting of a specific molecule (folic acid) for the recognition of cancer cells. Preliminary results on the surface functionalization of Ag nanocluster–silica composite films by folic acid and the ability of functionalized layers to selectively recognize the proper antibody will be discussed.

► Ag nanoclusters–silica thin films obtained by sputtering as possible sensing layers. ► Films present a typical LSPR absorption enhanced by thermal treatments (450 °C). ► Folic acid grafting to the films by silanization and carbodiimide activation. ► Folic acid functionalization for specific detection.