Remote magnetic actuation of micrometric probes for in situ 3D mapping of bacterial biofilm physical properties.
J Vis Exp
; (87)2014 May 02.
Article
em En
| MEDLINE
| ID: mdl-24837001
ABSTRACT
Bacterial adhesion and growth on interfaces lead to the formation of three-dimensional heterogeneous structures so-called biofilms. The cells dwelling in these structures are held together by physical interactions mediated by a network of extracellular polymeric substances. Bacterial biofilms impact many human activities and the understanding of their properties is crucial for a better control of their development - maintenance or eradication - depending on their adverse or beneficial outcome. This paper describes a novel methodology aiming to measure in situ the local physical properties of the biofilm that had been, until now, examined only from a macroscopic and homogeneous material perspective. The experiment described here involves introducing magnetic particles into a growing biofilm to seed local probes that can be remotely actuated without disturbing the structural properties of the biofilm. Dedicated magnetic tweezers were developed to exert a defined force on each particle embedded in the biofilm. The setup is mounted on the stage of a microscope to enable the recording of time-lapse images of the particle-pulling period. The particle trajectories are then extracted from the pulling sequence and the local viscoelastic parameters are derived from each particle displacement curve, thereby providing the 3D-spatial distribution of the parameters. Gaining insights into the biofilm mechanical profile is essential from an engineer's point of view for biofilm control purposes but also from a fundamental perspective to clarify the relationship between the architectural properties and the specific biology of these structures.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Técnicas Bacteriológicas
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Biofilmes
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Fenômenos Fisiológicos Bacterianos
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Magnetismo
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article