title: The non-linear mechanical properties of soft engineered biological tissues determined by finite spherical indentation.
abstract: The mechanical properties of soft biological tissues in general and early stage engineered tissues in particular limit the feasibility of conventional tensile tests for their mechanical characterisation. Furthermore, the most important mode in development of deep tissue injury (DTI) is compression. Therefore, an inverse numerical-experimental approach using a finite spherical indentation test is proposed. To demonstrate the feasibility of the approach indentation tests are applied to bio-artificial muscle (BAM) tissue. BAMs are cultured in vitro with (n = 20) or without (n = 12) myoblast cells to quantify the effect of the cells on the passive transverse mechanical properties. Indentation tests are applied up to 80% of the tissue thickness. A non-linear Neo-Hookean constitutive model is fitted to the experimental results for parameter estimation. BAMs with cells demonstrated both stiffer and more non-linear material behaviour than BAMs without cells.
authors.affiliation: Department of Biomedical Engineering, Eindhoven University of Technology, PO Box 513, 5600 MB Eindhoven, The Netherlands. m.a.j.cox@tue.nl
authors.forename: Martijn A J
authors.initials: MA
authors.lastname: Cox
authors.forename: Debby
authors.initials: D
authors.lastname: Gawlitta
authors.forename: Niels J B
authors.initials: NJ
authors.lastname: Driessen
authors.forename: Cees W J
authors.initials: CW
authors.lastname: Oomens
authors.forename: Frank P T
authors.initials: FP
authors.lastname: Baaijens
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D002478:Cells, Cultured; D003198:Computer Simulation; D004548:Elasticity; D020342:Finite Element Analysis; D051379:Mice; D009132:Muscles / Q000502:physiology*; D032446:Myoblasts / Q000502:physiology*; D017711:Nonlinear Dynamics; D033081:Shear Strength / Q000502:physiology*; D013314:Stress, Mechanical; D023822:Tissue Engineering / Q000379:methods