A combined computational fluid dynamics (CFD) and experimental approach to quantify the adhesion force of bacterial cells attached to a plane surface

Abstract

A three-dimensional model is developed to study the laminar shear flow past a bacterial cell attached to a plane surface. The induced hydrodynamic forces and torque exerted on the cell are computed to clarify the prevailing mechanisms involved in the detachment of model bacteria. Results are discussed in terms of drag and torque magnitude as a function of the angles defining the orientation of the cell. It is shown that reorientation and rolling of spheroid-shaped cells are favored. It is also confirmed that rod-shaped cells would tend to lie on the surface and become aligned with the flow. The model is used to quantify the adhesion force of spheroid Bacillus cereus spores to stainless steel, deduced from previously described experiments in a shear stress flow chamber. The magnitude of the predicted adhesion force is close to that obtained using atomic force microscopy under similar experimental conditions. (C) 2012 American Institute of Chemical Engineers AIChE J, 201

Estimation of the adhesive force distribution for the flagellar adhesion of Escherichia coli on a glass surface

“…To evaluate the order of magnitude of the force applied by the laminar flow, the ideal case of an individual spherical particle with a plate under a linear shear flow was assumed. The hydrodynamic drag force D when the cells were detached from the solid surface was estimated using the following equation [45,46]:…”

Experimental and computational analysis of a novel flow channel to assess the adhesion strength of sessile marine organisms

“…In general, laminar flow over an object in contact with an infinite plane produces three different external actions on the object: a drag force oriented in the main direction of the flow, F D , a lift force normal to the plane, F L , and a torque with axis parallel to the plane and orthogonal to the main direction of the flow, T [50,51]. In the ideal case of laminar infinite linear shear over a single spherical body, the drag, lift and torque exerted can be computed using the following expressions [52,53]:…”

Numerical Study of Flow inside the Micro Fluidic Cell Sense Cartridge

“…This tool has been employed here to study the influence of various non-rectangular geometrical configurations for biosensor sample receiving unit (cartridge) on the flow distribution and optimize the cartridge geometry. CFD approach has been employed by various researchers to predict the fluid stress, force, and torque on an adherent cell as a function of the fluid viscosity, channel height, cell size, and flow rate per unit width as well as to study the strength of cell adhesion in microchannels [5][6][7].…”