Authors: Nilsson, Daniel P. G. et al.

Journal: Scientific Reports (2025)

Institution: Department of Physics, Umeå University, Umeå, Sweden

Research Areas: Bacteriology

Summary: In this study, Nilsson et al. present the design and validation of a 3D-printed “Bio-Rocker” platform that provides tightly controlled temperature and adjustable rocking/shear-stress conditions to support biofilm growth under realistic fluid-shear and thermal regimes. The goal was to mimic industrial or environmental fluid conditions for biofilm cultivation, which standard incubation or rocker platforms cannot reliably replicate. They combined analytical and computational fluid-dynamics (CFD) modelling to estimate shear stress values at the surface and then grew biofilms of two bacterial strains under different temperatures and flow/shear regimes, comparing coverage, thickness, biomass, and robustness. Using HoloMonitor on unstained samples, they could measure biofilm thickness and coverage without destructive staining. They found that under static conditions very little biofilm adhered, whereas under moderate shear and flow conditions more robust biofilm formation occurred; sheared zones had monolayers or denser films depending on the shear magnitude. The authors conclude that the Bio-Rocker offers comparable performance to expensive commercial rocker/incubator systems yet at a lower cost and with open-source design.

Keywords: HoloMonitor biofilms, engineering, fluid dynamics