Effect of shear stress on the formation of bacterial biofilm in a microfluidic channel

Biofilms form an irregular network matrix that is surrounded by extracellular polymeric substrate (EPS). The architecture of biofilm plays an important role in protecting bacteria under physical, chemical, and biological stress. The shear stress is one of the major factors to construct stable bioflim. The experimental observation of biofilm formation on large-scale water flow has been limited because most of fluid pipe are water and sewer lines. This study presents the biofilm formation in a PDMS-based microfluidic channel which is able to simulate fluid pipes at small scale. We could characterize the hydrodynamics of the growth of single-species bacteria between biofilm formation and the external environmental factors. Particularly, the dynamics of biofilm formation confirms that biofilm, under the optimum shear stress, efficiently form a stable EPS structure which provides a mechanical shield against high-pressure fluidic flow.