The effect of different sizes of cross‐linked fibers of biodegradable electrospun poly(ε‐caprolactone) scaffolds on osteogenic behavior in a rat model in vivo

Abstract

A variety of biodegradable polymer scaffolds serving the purpose of mimicking the extracellular matrix have been studied; however, no effective recipe has yet been developed for scaffold pore size and overall percent porosity, which are optimal for cell penetration in vitro and tissue growth in vivo. Thus, this study reports the effect of poly(ε-caprolactone) (PCL) fiber size and scaffold porosity on the osteogenic behavior of scaffolds in a rat model in vivo. It was revealed that scaffolds with an average fiber size of 9.2 μm, and 4.05 μm, and combination of 0.6 μm submicrofibres (upper layer) with 9.2 μm microfibres (bottom layer) in hybrid two-layer scaffolds behave significantly differently with respect to macrophage reactions and tissue regeneration in a rat model in vivo. Poor macrophage response at implantation tests into the bone tissue in vivo reveals the advantages of microfibrous PCL scaffolds with a fiber size of 4.05 μm and hybrid scaffolds with submicro-and microfibres for stimulation of reparative osteogenesis over microfibrous scaffolds with a fiber size of 9.2 μm. The combination of submicro-and microfibrous layers in hybrid scaffolds provides an opportunity to control the shape and density of bone trabeculae during regeneration processes in vivo.

Magnetoactive Composite Conduits Based on Poly(3-hydroxybutyrate) and Magnetite Nanoparticles for Repair of Peripheral Nerve Injury

“…The total porosity of the scaffolds was computed by the gravimetric method reported previously . Wall thickness values of the conduits were measured by means of ImageJ in optical photographs of the conduits’ cross sections, and the total porosity was calculated using eq normalp orosity 0.25em ( % ) = ( 1 − a pparent density 0.25em ( g cm − 3 ) b ulk density 0.25em ( g cm − 3 ) ) · 100 % The apparent density of the conduits was calculated as follows normala pparent density false( g cm − 3 false) = ( c onduit mass false( normalg false) w all thickness false( cm false) · w all area 0.25em ( cm 2 ) ) The bulk density of pure PHB was assumed to be 1.2 g cm –3 (ref ), while the bulk density of the PHB/Fe 3 O 4 –CA composite (ρ) was calculated using eq ρ = ( m PHB + m magnetite ) / ( m PHB ρ PHB + m magnetite ρ magnetite ) ...…”

“…The total porosity of the scaffolds was computed by the gravimetric method reported previously. 21 Wall thickness values of the conduits were measured by means of ImageJ in optical photographs of the conduits' cross sections, and the total porosity was calculated using eq 1 porosity (%) 1 apparent density (g cm ) bulk density (g cm ) 100%…”

The microchamber wound coatings effect on the microcirculatory reactions dynamics in the full-thickness skin defect area in white rats

“…При разработке полимерных раневых покрытий особое значение имеет выявление возможных негативных гистопатогеннных эффектов, т. е. оценка их биосовместимости, наличие которой, в конечном итоге, определяет практическую применимость продукта [10]. При микро-и наноструктурировании синтетических полимеров биосовместимость разрабатываемой конструкции может отличаться от таковой у входящих в ее состав материалов, что обусловлено влиянием размеров отдельных составляющих и архитектоникой биодеградируемого изделия, а также технологическими особенностями его изготовления [11]. В этой связи возникает необходимость исследований in vivo микрокамерных покрытий на моделях полнослойной кожной раны у животных.…”

Electrowriting of silk fibroin: Towards 3D fabrication for tissue engineering applications

“…In TE there is an increasing demand to engineer structures that closely mimic the features of native tissues and organs. Although electrospinning is capable of producing fibers with small diameters, it fails to adequately support cell–cell interactions, migration, remodeling, and production of new ECM in a spatially controlled manner 20,21 . On the other hand, EW can produce 3D patterned structures with defined placement of fibers thus offering new opportunities for generation of constructs that can exhibit functions at organ and tissue level 22 …”

“…Although electrospinning is capable of producing fibers with small diameters, it fails to adequately support cell-cell interactions, migration, remodeling, and production of new ECM in a spatially controlled manner. 20,21 On the other hand, EW can produce 3D patterned structures with defined placement of fibers thus offering new opportunities for generation of constructs that can exhibit functions at organ and tissue level. 22 Brown et al 23 have extensively studied EW for biodegradable thermoplastic materials including poly(ε-caprolactone) (PCL).…”