Only last spring the SARS epidemic sent a shiver of fear around the globe. Now scientists working at the Institute of Virology at the University Hospital of Philipps University Marburg discovered that the viruses responsible for the severe acute respiratory syndrome (SARS) lose their terror on surfaces coated with special nanoparticles.
These nanoparticles, only a few millionths of a millimeter in diameter, consist of titanium dioxide encased in a nano-thin layer of silver. In laboratory tests they proved capable of inactivating the coronaviruses which cause SARS in addition to bacteria and fungi. The Marburg researchers found that, after four hours of contact with the coating, the infectiousness of the viruses had decreased by more than two log steps. The nanoparticles have an especially large specific surface of around 200 sqm per gram. Owing to their silver coating, the particles release silver ions over long periods of time; these ions effectively deactivate pathogenic bacteria, fungi and viruses but are harmless for human beings.
The effectiveness of the coating against SARS was confirmed during a study commissioned by ItN Nanovation GmbH, a nanotechnology company located in Saarbrücken. The objective of the study, which was carried out by the well known German research institute in Marburg, was to find additional applications for ItN’s microbicidal nanoparticles.
The nano-powder with the brand name Nanozid is added to paints and lacquers used to coat operating tables, door knobs and door handles in hospitals (e.g. "clean rooms”) and surfaces in sanitary facilities. In addition to their obvious utility in the clinical sector, biocidal coatings have numerous applications in the food and beverage industries and in HVAC systems, which frequently serve as vehicles for the spread of infectious diseases.