An electrospun triphasic nanofibrous scaffold for bone tissue engineering

Abstract

A nanofibrous triphasic scaffold was electrospun from a mixture of polycaprolactone (PCL), type-I collagen and hydroxyapatite nanoparticles (nano-HA) with a mixture dry weight ratio of 50/30/20, respectively. Scaffolds were characterized by evaluating fiber morphology and chemical composition, dispersion of HA particles and nanoindentation. Scanning electron microscopy revealed fibers with an average diameter of 180 +/- 50 nm, which coincides well with the collagen fiber bundle diameter characteristic of the native extracellular matrix of bone. The triphasic fibers, stained with calcein and imaged with confocal microscopy, show a uniform dispersion of apatite particles throughout their length with minor agglomeration. Scaffold fibers of triphasic (50/30/20), collagen/nano-HA (80/20), PCL/nano-HA (80/20), pure PCL and pure collagen were each pressure consolidated into non-porous pellets for evaluation by transmission electron microscopy and nanoindentation. While the majority of apatite particles are uniformly dispersed having an average size of 30 nm, agglomerated particles as large as a few microns are sparsely distributed. Nanoindentation of the pressure-consolidated scaffolds showed a range of Young's modulus (0.50-3.9 GPa), with increasing average modulus in the order of (PCL < PCL/nano-HA < collagen < triphasic < collagen/nano-HA). The modulus data emphasize the importance of collagen and its interaction with other components in affecting mechanical properties of osteoconductive scaffolds.

Development of antimicrobial PCL/nanoclay nanocomposite films with enhanced mechanical and water vapor barrier properties for packaging applications

“…A Poisson's ratio of 0.47 is used in all modulus calculations [66]. A good agreement is found between our PCL Young's modulus value and literature [67]. As shown in Table 4, an increase in modulus and hardness is obtained for the PCL nanocomposites relative to those of neat PCL.…”

Effect of Molecular Weight on Electro Spun Pcl Based Composite Fibrous Mats

“…In both molecular weight regimes, the effect of HA seems to be the same in increasing the overall diameter of the fibres. This is generally observed in Electrospinning of composites [16] The XRD patterns of the electrospun mats and HA are shown in (Figure 2). Crystalline PCL has an orthorhombic crystal structure with XRD peaks around 21.7° and 23.7° along with a smaller shoulder at 22° corresponding to the (110), (200) and (111) planes.…”

Processing Technologies for 3D Nanostructured Tissue Engineering Scaffolds

“…[94] Natural polymers, such as silk, [95] thermally responsive hydroxybutyl chitosan (HBC), [96] combinations of chitosan and polyethylene oxide (PEO), [97] chitosan and poly(ecaprolactone), [98] and alginate-based PEO [99] have also been used to produce scaffolds via electrospinning. The technique was also used to fabricate nanofibrous triphasic scaffolds from a mixture of PCL, type-I collagen, and n-HAps [100] and from combination of poly(lactide-co-glycolide) acid (PLGA), n-HA, and type I collagen. [101] Other studies have shown that human MSCs cultured on eletrospun nanoscale TCP/PLGA composite fibers exhibited very high bioactivity and showed rapid cell differentiation, confirming improved cell stimulation by the nanostructured composites.…”