title: Modeling the fluid-dynamics and oxygen consumption in a porous scaffold stimulated by cyclic squeeze pressure.
abstract: The architecture and dynamic physical environment of tissues can be recreated in-vitro by combining 3D porous scaffolds and bioreactors able to apply controlled mechanical stimuli on cells. In such systems, the entity of the stimuli and the distribution of nutrients within the engineered construct depend on the micro-structure of the scaffolds. In this work, we present a new approach for optimizing computational fluid-dynamics (CFD) models for the investigation of fluid-induced forces generated by cyclic squeeze pressure within a porous construct, coupled with oxygen consumption of cardiomyocytes. A 2D axial symmetric macro-scaled model of a squeeze pressure bioreactor chamber was used as starting point for generating time dependent pressure profiles. Subsequently the fluid movement generated by the pressure fields was coupled with a complete 3D micro-scaled model of a porous protein cryogel. Oxygen transport and consumption inside the scaffold was evaluated considering a homogeneous distribution of cardiomyocytes throughout the structure, as confirmed by preliminary cell culture experiments. The results show that a 3D description of the system, coupling a porous geometry and time dependent pressure driven flow with fluid-structure-interaction provides an accurate and meaningful description of the microenvironment in terms of shear stress and oxygen distribution than simple stationary 2D models.
authors.affiliation: Laboratory of Biological Structure Mechanics, Chemistry, Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Ferroni
authors.affiliation: Research Center E. Piaggio, University of Pisa, Via Diotisalvi 2, 56122 Pisa, Italy.
authors.forename: Serena
authors.initials: S
authors.lastname: Giusti
authors.affiliation: INEB-Instituto Nacional de Engenharia Biomédica, Universidade do Porto, Portugal & ICBAS- Instituto de Ciências Biomédicas Abel Salazar, 4150-180 Porto, Portugal.
authors.forename: Diana
authors.initials: D
authors.lastname: Nascimento
authors.affiliation: INEB-Instituto Nacional de Engenharia Biomédica, Universidade do Porto, Portugal & ICBAS- Instituto de Ciências Biomédicas Abel Salazar, 4150-180 Porto, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Silva
authors.affiliation: Laboratory of Biological Structure Mechanics, Chemistry, Materials and Chemical Engineering Department "Giulio Natta", Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milan, Italy.
authors.forename: Federica
authors.initials: F
authors.lastname: Boschetti
authors.affiliation: Research Center E. Piaggio, University of Pisa, Via Diotisalvi 2, 56122 Pisa, Italy. Electronic address: arti.ahluwalia@centropiaggio.unipi.it.
authors.forename: Arti
authors.initials: A
authors.lastname: Ahluwalia
mesh_terms: D002460:Cell Line; D057446:Hydrodynamics; D008422:Materials Testing / Q000295:instrumentation*; D008954:Models, Biological; D010101:Oxygen Consumption; D016062:Porosity; D011312:Pressure; D013314:Stress, Mechanical; D023822:Tissue Engineering; D054457:Tissue Scaffolds
keywords: 3D porous cryogel; Bioreactor; CFD model; Cardiac tissue engineering; Fluid–structure interaction; Oxygen consumption