title: Bacteria Delay the Jamming of Particles at Microchannel Bottlenecks.
abstract: Clogging of channels by complex systems such as mixtures of colloidal and biological particles is commonly encountered in different applications. In this work, we analyze and compare the clogging mechanisms and dynamics by pure and mixture suspensions of polystyrene latex particles and Escherichia coli by coupling fluorescent microscopic observation and dynamic permeability measurements in microfluidic filters. Pure particles filtration leads to arches and deposit formation in the upstream side of the microfilter while pure bacteria form streamers in the downstream zone. When mixing particle and bacteria, an unexpected phenomenon occurs: the clogging dynamics is significantly delayed. This phenomenon is related to apparent "slippery" interactions between the particles and the bacteria. These interactions limit the arches formation at the channels entrances and favour the formation of dendritic structures on the pillars between the channels. When these dendrites are eroded by the flow, fragments of the deposit are dragged towards the channels entrances. However, these bacteria/particles clusters being lubricated by the slippery interactions are deformed and stretched by the shear thus facilitating their passage through the microchannels.
authors: Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France.
authors: Zenamarkos Bantie
authors: ZB
authors: Sendekie
authors: Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France.
authors: Arthur
authors: A
authors: Gaveau
authors: Soft Matter, Fluidics and Interfaces, MESA+ Institute for Nanotechnology, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
authors: Rob G H
authors: RG
authors: Lammertink
authors: Laboratoire de Génie Chimique, Université de Toulouse, CNRS, INPT, UPS, Toulouse, France.
authors: Patrice
authors: P
authors: Bacchin
mesh_terms: D004926:Escherichia coli / Q000502:physiology*; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation*; D008863:Microspheres; D010316:Particle Size; D011137:Polystyrenes / Q000737:chemistry; D013499:Surface Properties
chemical_list: D011137:Polystyrenes