The Effect of Surface Treatment on the Antibacterial Properties of Wood and the Possibility to Detect the Antibacteriality with Fluorescence Method

Wood is a widely used indoor material, and thus it is important to consider wood performance in microbial cross contamination via surfaces. In this study, both untreated and surface- treated wood materials were studied by simulating airborne bacterial contamination and evaluating the number of bacterial colonies on the material surfaces. The materials studied were untreated pine heartwood and sapwood, spruce, silver birch, and glass as a reference. The intensity of UV-excited fluorescence was measured to find the most antibacterial Scots pine heartwood. The coatings used were varnish and wax for Scots pine sapwood. The surface roughness of all material types was compared, and it was found to be uniform. All untreated wood surfaces had less viable bacterial colonies at all time points compared to the glass reference, and the surface treated samples did not differ from the glass reference indicating that the antibacterial properties of wood were blocked by both varnish and wax. The fluorescence method was practical to use, but wider testing will be needed to validate it more thoroughly. The results indicate also that silver birch has similar antibacterial properties as pine and spruce and hence should be studied further.