Biofilm formation on the surface of ceramic tiles

The aim of the study was to investigate the formation of biofilm on the sur face of ceramic tiles, widely present in public and private buildings, usin g six parallel flow chambers. Our flow system was conceived and made to compare biofilm results by parall el distributed rectangular tiles. The tiles, divided into two identical A and B sections, were placed within the flow chambers. Biofilm formation was performed after 72 h and was quantified by viable cou nts of bacteria. Average viable counts ranged from 1.1 x10(7) to 7.3x10(7) cfu cm(-2) and from 1.1x10(7) to 5.8x10(7) cfu cm(-2) respectively for biof ilm A and B sections. As statistical analysis does not show significant dif ferences, we can conclude that biofilms obtained were so similar to each ot her that they confirmed the system reproducibility. Our next step will be to use our system to study Legionella pneumophila and to evaluate the efficacy of antibacterial agents.