title: Effect of biomimetic conditions on mechanical and structural integrity of PGA/P4HB and electrospun PCL scaffolds.
abstract: The selection of an appropriate scaffold represents one major key to success in tissue engineering. In cardiovascular applications, where a load-bearing structure is required, scaffolds need to demonstrate sufficient mechanical properties and importantly, reliable retention of these properties during the developmental phase of the tissue engineered construct. The effect of in vitro culture conditions, time and mechanical loading on the retention of mechanical properties of two scaffold types was investigated. First candidate tested was a poly-glycolic acid non-woven fiber mesh, coated with poly-4-hydroxybutyrate (PGA/P4HB), the standard scaffold used successfully in cardiovascular tissue engineering applications. As an alternative, an electrospun poly-epsilon-caprolactone (PCL) scaffold was used. A 15-day dynamic loading protocol was applied to the scaffolds. Additionally, control scaffolds were incubated statically. All studies were performed in a simulated physiological environment (phosphate-buffered saline solution, T=37 degrees C). PGA/P4HB scaffolds showed a dramatic decrease in mechanical properties as a function of incubation time and straining. Mechanical loading had a significant effect on PCL scaffold properties. Degradation as well as fiber fatigue caused by loading promote loss of mechanical properties in PGA/P4HB scaffolds. For PCL, fiber reorganization due to straining seems to be the main reason behind the brittle behavior that was pronounced in these scaffolds. It is suggested that those changes in scaffolds' mechanical properties must be considered at the application of in vitro tissue engineering protocols and should ideally be taken over by tissue formation to maintain mechanically stable tissue constructs.
authors: Division of Biomechanics and Tissue Engineering, Department of Biomedical Engineering, Eindhoven University of Technology, P.O. Box 513, Eindhoven 5600 MB, The Netherlands. leda.kloudas@rice.edu
authors: Leda
authors: L
authors: Klouda
authors: Claudia M
authors: CM
authors: Vaz
authors: Anita
authors: A
authors: Mol
authors: Frank P T
authors: FP
authors: Baaijens
authors: Carlijn V C
authors: CV
authors: Bouten
mesh_terms: D020341:Absorbable Implants; D032701:Biomimetics / Q000295:instrumentation; D002152:Calorimetry, Differential Scanning; D006885:Hydroxybutyrates / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D008954:Models, Biological; D011091:Polyesters / Q000737:chemistry*; D011100:Polyglycolic Acid / Q000737:chemistry*; D013314:Stress, Mechanical; D013718:Tensile Strength; D054457:Tissue Scaffolds / Q000737:chemistry*
chemical_list: D006885:Hydroxybutyrates; D011091:Polyesters; C107955:poly(4-hydroxybutanoate); C016240:polycaprolactone; D011100:Polyglycolic Acid
references: Circulation. 2000 Nov 7;102(19 Suppl 3):III44-9
references: 11082361
references: J Biomech Eng. 2000 Jun;122(3):210-5
references: 10923287
references: J Control Release. 2003 Apr 29;89(2):341-53
references: 12711456
references: Tissue Eng. 2001 Dec;7(6):679-89
references: 11749726
references: Thorac Cardiovasc Surg. 2003 Apr;51(2):78-83
references: 12730815
references: Tissue Eng. 2000 Feb;6(1):75-9
references: 10941203
references: J Biomed Mater Res. 2001 May;55(2):203-16
references: 11255172
references: Eur J Cardiothorac Surg. 2001 Jul;20(1):164-9
references: 11423291
references: Tissue Eng. 1996 Spring;2(1):61-74
references: 19877952
references: Biomaterials. 2000 Dec;21(24):2529-43
references: 11071603
references: Biomaterials. 2004 Jan;25(2):315-25
references: 14585719
references: J Biomed Mater Res. 2002 Jun 15;60(4):613-21
references: 11948520
references: Science. 1999 Apr 16;284(5413):489-93
references: 10205057
references: J Biomed Mater Res A. 2004 Sep 15;70(4):603-14
references: 15307165
references: Biomacromolecules. 2002 Mar-Apr;3(2):232-8
references: 11888306
references: J Biomater Sci Polym Ed. 2006;17(1-2):77-89
references: 16411600
references: Nat Biotechnol. 1999 Oct;17(10):979-83
references: 10504698
references: J Biomed Mater Res. 2001;58(4):401-5
references: 11410898
references: ASAIO J. 2000 Jan-Feb;46(1):107-10
references: 10667727