Biofilms in Space: Biofilm Control Using Nanoparticulate Photocatalytic Thin Films

A number of surfaces have been shown to foul due to biofilm formation during space flight. Affected systems include water and air processing components, animal experimentation chambers, and cabin surfaces. This fouling not only reduces crew efficiency by increasing cleaning times, but also can pose a significant health risk for both humans and animals.

When illuminated with near-UV light, nanoparticulate thin films of titanium dioxide fixed to surfaces generate active oxygen radicals resulting in complete oxidation of organic compounds adsorbed at the surface. This characteristic makes photocatalytic oxidation a potentially attractive option for preventing biofilm formation on these surfaces. In fact, recent work has shown this technology to be effective for the sterilization of surfaces in hospitals and other areas where biological contamination is of great concern. However, the conditions onboard the shuttle and space station are very specific. The P.I. will obtain data showing the effectiveness of photocatalytic oxidation in environments resembling those onboard the shuttle and space station, and subsequently present NASA with an attractive biofilm control strategy.

The proposed research will study the effectiveness of TiO₂-mediated photo-oxidation for the prevention of biofilm formation on stainless steel, a material commonly used in animal and plant test chambers and human living and working quarters aboard spacecraft. The photocatalytically active surface will be produced by coating stainless steel coupons with a thin film of TiO₂ prepared using sol-gel processing techniques. The rates of initial biofilm formation on photocatalytic and control surfaces will be studied. Specific attention will be paid to the effects of light intensity and lamp type.

Contact Information

Mail:	Dr. James E. Duffy
	Chemical Engineering Department
	Montana State University
	Bozeman, MT 59717