Determination of biofilm mechanical properties from tensile tests performed using a micro-cantilever method.
Recently, a micro-cantilever method was introduced for measuring the ultimate tensile strength of intact bacterial biofilms. Herein, is reported the analysis of the video files from the testing of a 4-day-old Staphylococcus epidermidis biofilm to determine the elastic modulus, toughness, and failure strain. Elastic modulus (1270+/-280 Pa) was within the range of previously reported values (17-6000 Pa). The high failure strains (240+/-16%) indicate the substantial ductility of bacterial biofilms. In addition, the toughness of the biofilm sample was determined from the area under the stress-strain plot (2.8+/-0.44 kJ m(-3)). Thus, it was demonstrated that the micro-cantilever test video files can be used for the determination of other mechanical property parameters besides ultimate tensile strength.
Aggarwal
Srijan
S
Department of Civil Engineering, University of Minnesota, Minneapolis, MN 55455-0220, USA.
Hozalski
Raymond M
RM
D001422:Bacterial Adhesion; D001431:Bacteriological Techniques / Q000379:methods; D018441:Biofilms / Q000254:growth & development*; D001696:Biomechanical Phenomena; D004548:Elasticity; D008954:Models, Biological; D013212:Staphylococcus epidermidis / Q000254:growth & development*; D013499:Surface Properties; D013718:Tensile Strength