Short answer : Silver ions in all GUARDXPRO surface protectors stop bacteria multiplying, Stop them from getting nutrients inside their body and stop them from being able to produce energy.
Geeky answer : GUARDXPRO prevents the biofilm from reforming (with silver ions that destroy the so-called solitary, free-floating planktonic bacteria, for instance) During cleaning operations, as well as in the presence of humidity, silver ions are released from the top layer of the film.
These ions come into contact with the bacteria, blocking their metabolism and/or interrupting their proliferation mechanism, leading to their destruction.