Hydrodynamic Interactions and Biofilm Dynamics

Biofilms are surface-attached assemblages of microorganisms embedded within a self-produced extracellular matrix. In natural and engineered settings—ranging from medical devices and water distribution systems to industrial pipelines—fluid flow governs the transport of nutrients, signalling molecules and metabolic by-products and imposes mechanical forces that shape biofilm architecture, resilience and dispersal. Hydrodynamic parameters such as shear stress, velocity gradients and flow fluctuations modulate key stages of the biofilm life cycle: initial adhesion, microcolony formation, maturation and detachment. These processes exhibit complex feedbacks, whereby the developing biofilm alters local flow fields, generating zones of reduced shear that foster spatial heterogeneity and niche differentiation. Advances in microfluidic technologies have enabled precise control of microscale flow environments, revealing how physical cues interact with microbial behaviour to determine community composition, mechanical properties and phenotypic diversity. A deeper understanding of these hydrodynamic interactions informs strategies to prevent biofouling, optimise bioreactor performance and design anti-biofilm surfaces with wide-ranging applications in environmental management, industrial processing and healthcare.

Research from Nature Portfolio

Recent studies have demonstrated that under controlled microfluidic flow, individual Escherichia coli cells exhibit bistable growth dynamics. At higher shear rates a subpopulation enters growth arrest while simultaneously strengthening adhesion via bipolar attachment, whereas actively dividing cells adhere asymmetrically. This dual strategy balances sustained colonisation with enhanced tenacity in fluctuating flows. In complementary work, experiments with motile Pseudomonas aeruginosa and Escherichia coli in curved microchannels reveal that velocity gradients drive preferential attachment on leeward regions of non-planar surfaces. A mathematical model, incorporating cell morphology and swimming traits, captures how streamlines direct bacteria to specific sites, altering both the magnitude and spatial pattern of initial colonisation.

Hydrodynamic Interactions and Biofilm Dynamics publication trend

The graph below shows the total number of articles in hydrodynamic interactions and biofilm dynamics across all publications each year (not limited to Nature Index journals).

Technical terms

Shear stress: Tangential force per unit area exerted by fluid flow on a surface, influencing cell adhesion and detachment.

Extracellular polymeric substances (EPS): Self-produced matrix of polysaccharides, proteins and nucleic acids that embeds and protects biofilm cells.

Microfluidics: Technology for manipulating small volumes of fluid in channels with micrometre dimensions, enabling precise control of hydrodynamic conditions.

Phenotypic heterogeneity: Coexistence of distinct cellular behaviours within a genetically identical population in response to environmental cues.

Microvortex: Localised, small-scale swirling flow structure generated within microchannels that alters transport and attachment of cells.

References

1. Fluid flow drives phenotypic heterogeneity in bacterial growth and adhesion on surfaces. Nature Communications (2024).
2. The effect of flow on swimming bacteria controls the initial colonization of curved surfaces. Nature Communications (2020).
3. Microfluidic investigation of the impacts of flow fluctuations on the development of Pseudomonas putida biofilms. npj Biofilms and Microbiomes (2023).
4. Microfluidic Platform with Precisely Controlled Hydrodynamic Parameters and Integrated Features for Generation of Microvortices to Accurately Form and Monitor Biofilms in Flow. ACS Biomaterials Science & Engineering (2024).