Influence of membrane surface properties on the behavior of initial bacterial adhesion and biofilm development onto nanofiltration membranes.

In order to investigate biofouling problems, the fundamental behaviors of initial bacterial adhesion and biofilm development on four different nanofiltration (NF) membranes were evaluated using Pseudomonas aeruginosa PAO1 as a model bacterial strain. Initial cell adhesion was considerably higher on an aromatic polyamide-based NF membrane with a hydrophobic and rough surface, whereas cell aggregation on a polypiperazine-based NF membrane with a relatively hydrophilic and smooth surface was lower. Moreover, significant differences in the structural heterogeneity of the biofilms were observed among the four NF membranes. This study shows that the surface roughness and hydrophobicity of a membrane play an important role in determining initial cell adhesion, aggregation and favorable localization sites for colony formation. In addition, it was found that biofilm development was strongly influenced by the surface morphology of a membrane.