Antimicrobial ecological waterborne paint based on novel hybrid nanoparticles of zinc oxide partially coated with silver

Antimicrobial activity of Zinc oxide partially coated with silver nanoparticles produced by Flame Spray Pyrolysis (FSP) as an additive to include in waterborne paints with promising applications in areas as schools, clinics or hospital environments and in food industry equipment and facilities has been demonstrated. Due to the current increase of multi-resistant microorganisms, the results obtained in this research would enable an enhanced sanitary conditions to avoid health problems of professionals and improve the Hazard Analysis Critical Control Point (HACCP) in the Food Industry like a way to control the biofilm formation on surfaces and beyond. The nanomaterial was prepared by the use of Flame Spray Pyrolysis process obtaining nanoparticles of about 35 nm coated with ca. 5% (w/w) of silver (Ag). Antimicrobial trials showed that these ZnO-Ag nanoparticles has a potential effect against different bacteria (Staphylococcus aureus, Pseudomona spp, Salmonella spp, Bacillus subtilis, Listeria monocytogenes) and molds as Aspergillus niger. Furthermore, these nanoparticles were evaluated as an antimicrobial waterborne paints additive, and formulations with 0,15% (w/w) showed > 5 nun inhibition zone against the main bacteria and molds tested.