Fatigue prediction in fibrin poly-ε-caprolactone macroporous scaffolds

Abstract

Tissue engineering applications rely on scaffolds that during its service life, either for in-vivo or in vitro applications, are under mechanical solicitations. The variation of the mechanical condition of the scaffold is strongly relevant for cell culture and has been scarcely addressed.Fatigue life cycle of poly-ε-caprolactone, PCL, scaffolds with and without fibrin as filler of the pore structure were characterized both dry and immersed in liquid water. It is observed that the there is a strong increase from 100 to 500 in the number of loading cycles before collapse in the samples tested in immersed conditions due to the more uniform stress distributions within the samples, the fibrin loading playing a minor role in the mechanical performance of the scaffolds.

In vitromechanical fatigue behavior of poly‐ɛ‐caprolactone macroporous scaffolds for cartilage tissue engineering: Influence of pore filling by a poly(vinyl alcohol) gel

“…This double porous structure results in and overall high porosity (83.4±2.6% 6 ) and has been previously proposed for cartilage and bone replacement [30][31][32] . Such structure favors scaffold permeability to nutrients and waste products of cell metabolism and can be used to retain active components 11,33,34 .…”

“…However, accurate fitting to the Morrow´s energy model is just possible up to 200 loading-unloading cycles. The deviation for larger number of cycles occurs both for dry and pristine PCL 6 samples. This fact, should be related to complex changes in the porous structure and local interactions among the different phases (PCL, PVA and water).…”

“…Sample preparation: PCL scaffolds were prepared as previously described elsewhere 6 . Briefly, PCL was dissolved in dioxane (25% w/v) and this solution was mixed with PEMA microspheres…”

“…For dry scaffolds, the mechanical properties will depend mainly on the inner morphology, in particular, pore size and polymer wall thickness and interconnectivity 5 . On the other hand, when the scaffold is immersed in an aqueous media, there are other factors that contribute for scaffold mechanical behavior as well, such as hydrodynamics and permeability inside the porous structure 5,6 . Water is known for its low compressibility and any factor limiting water permeation through the material will increase apparent scaffold stiffness and therefore the influence of liquid media cannot be disregarded 6 .…”

An experimental fatigue study of a porous scaffold for the regeneration of articular cartilage

“…A perfect elastomer does not show any hysteresis curve, the loading and unloading path are identical and no energy is dissipated (Love 1927) (Ewing 1889). In previous work (Panadero et al 2013) a macro and micro porous PCL scaffold was filled with a fibrin gel and mechanically tested for fatigue predictions up to 1 000 cycles. The hysteresis energy was calculated and with a mathematical model it was shown that filling the PCL scaffold with water or fibrin improved the fatigue life of the scaffold.…”