Aditivos Cerámicos has formulated a product from silver nanoparticles that can create an antibacterial effect on the treated ceramic surfaces and that provides permanent bacteriostatic and hygienic properties to the glazed surface.
The effect of the silver is seen in the following picture:
Treatment of cells with Ag+ results in DNA condensation and cell wall damage.
Silver particles destroy cell membrane by contact and all microorganisms die. If is also affecting replication because DNA is condensed and destroyed.
HOW IT IS APPLIED?
NANOSILVER AG is a liquid that contains silver in the form of nanoparticles (sizes below 5 nm). The particles are coated by polymer to remain stable.
NANOSILVER AG additive is added in the glaze at low rate (between 0,2 and 0.5%). The product has no effect on rheology of the glaze and it doesn’t create any kind of problem like bubbles, application or any other effect.
After firing it has no effect on tonalities, the product will remain transparent and the finished product doesn’t suffer any change.
HOW CAN BE TESTED THE ANTIBACTERIAL EFFECT?
The most common method to determine bacteriostatic effect of surfaces is JIS Z 2801 (Japanese Industrial Standard). This is the method followed by certified laboratories.
The values of efficiency are given depending on cfu (colony forming units) of the agar plates. Cfu values are related to the remaining bacteria that were surviving (still alive) in the tile surface. After being transferred to the plate, bacteria start developing forming colonies (yellow circles over the agar gel material).
HOW IS THE EFFICIENCY OF NANOSILVER AG?
Following the method, after preparing the ceramic pieces, the antibacterial effect is tested by inoculation of bacteria over the tile surface and then surviving bacteria are transferred to a agarose plate culture. In this plate. surviving bacteria can grow easily under optimal conditions of humidity and temperature.
After letting the surviving bacteria grow, the colony forming units are measured to see how bacteria can survive over the surface. This is an example when testing NANOSILVER AG:
The agar plate on the left comes from the NON-TREATED tile (as control), the plate on the right comes from the treated tile.
The number of c.f.u is higher in the left plate (there are many bacteria) than in the right plate (there are no surviving bacteria). NANOSILVER AG has a very high efficiency as antibacterial protection in ceramic tiles.