The use of composites of cellulose nanofibrils (NFC)/nanoparticles (Nps) of Silver and Gold is an interesting approach to produce papers with antimicrobial and mechanical characteristics eligible for packaging and filter of air purifying.

BiomediCol created papers with strong bacteriostatic and bactericidal activity against di K. Pneumoniae e S.Aureus.

The nanocomposites are designed by Electrostatic Assembly (EA) of nanoparticles of Ag/Au on NFC using in sequence a cationic (PDDA), an anionic (PSS) and a cationic (PDDA) polyelectrolyte.

The bacteriostatic and partially bactericidal activity has been detected for concentration of nanoparticles > 0,1% w/w against S.Aureus and concentration > 0,018% w/w against K. Pneumoniae

Brightness, air permeability and mechanical (strength e Bursting strength) properties of the paper treated with NFC/NPs have been investigated: a worsening of the brightness, not relevant for applications of packaging or filters for air purifying, an improving of air permeability and a retention of mechanical properties, compared to not treated paper, have been observed.

Moreover, BiomediCol applied silver nanoparticles even on ceramic supports. The silver ions, released by the coated support, act on the micro-organisms, destroying the cellular walls, preventing the reproduction and stopping the metabolism. To obtain the antibacterial or bacteriostatic effect, the silver ions must be available on the tile surface.