Inhibitory effects of single-walled carbon nanotubes on biofilm formation from Bacillus anthracis spores.

This study reports the inhibitory effect of single walled carbon nanotubes (SWCNTs) on biofilm formation from Bacillus anthracis spores. Although the presence of 50 to 100 μg ml(-1) of SWCNTs in the suspension increased spore attachment in the wells of 96-well plates, the presence of 200 μg ml(-1) of SWCNTs in the germination solution decreased the germination percentage of the attached spores by 93.14%, completely inhibiting subsequent biofilm formation. The inhibition kinetics of 50 μg ml(-1) SWCNTs on biofilm formation showed that this concentration inhibited biofilm formation by 81.2% after incubation for 48 h. SWCNT treatment in the earlier stages of biofilm formation was more effective compared to treatment at later stages. Mature biofilms were highly resistant to SWCNT treatment.