[Microscope observation of the microbial distribution on the wall of different pipe material in water supply system]

Scanning electron microscope, atomic force microscope and confocal laser scanning microscope were used to observe the microbial distribution and biofilm structure on the surface of stainless steel plugs and the wall of PPR pipe in the water distribution system. The results show that, it is not easy for microbial to attach on the surface of stainless steel plugs. Little bacteria was observed in a short period of time (less than 3 months). Bacteria can be easily observed in the sediment of the PPR pipe wall at the end of water supply system. Bacteria was tightly adhered to the surface of the PPR pipe wall. Combination of scanning electron microscope and atomic force microscope is a practical way to observe the surface structure of discontinuous biofilm in the pipeline. The inner and three-dimensional structure of the pipe biofilm can be simultaneously observed by confocal laser scanning microscope.