Dermal fibroblast infiltration of poly(ε-caprolactone) scaffolds fabricated by melt electrospinning in a direct writing mode

Abstract

Melt electrospinning in a direct writing mode is a recent additive manufacturing approach to fabricate porous scaffolds for tissue engineering applications. In this study, we describe porous and cell-invasive poly (ε-caprolactone) scaffolds fabricated by combining melt electrospinning and a programmable x-y stage. Fibers were 7.5 ± 1.6 µm in diameter and separated by interfiber distances ranging from 8 to 133 µm, with an average of 46 ± 22 µm. Micro-computed tomography revealed that the resulting scaffolds had a highly porous (87%), three-dimensional structure. Due to the high porosity and interconnectivity of the scaffolds, a top-seeding method was adequate to achieve fibroblast penetration, with cells present throughout and underneath the scaffold. This was confirmed histologically, whereby a 3D fibroblast-scaffold construct with full cellular penetration was produced after 14 days in vitro. Immunohistochemistry was used to confirm the presence and even distribution of the key dermal extracellular matrix proteins, collagen type I and fibronectin. These results show that melt electrospinning in a direct writing mode can produce cell invasive scaffolds, using simple top-seeding approaches.

Reinforcement of hydrogels using three-dimensionally printed microfibres

“…With this unique and new 3D-printing technique, pre-set network architectures can be realized in a direct writing mode 34 . This technique allows fibres to be printed well below the limits of classical melt-extrusion-based 3D-printing technologies such as fused deposition modelling 39 , with filament diameters as small as 5 mm, instead of 100 mm or larger 35 .…”

“…However, a disadvantage of traditional solution electrospinning techniques is the limited control over network architecture. Recently, melt electrospinning has been used in a direct writing mode, and may overcome this limitation, with the layer-by-layer assembly of the low-diameter fibres, permitting tight control over the network architecture 34,35 .…”

Fibre pulsing during melt electrospinning writing

“…MEW is solvent-free -therefore the need to print within a fume hood or to use special equipment to remove volatile chemicals is not required, and solvent accumulation in fibres does not occur. Another benefit of MEW is that small fibre diameters lead to flexible constructs that enable even relatively rigid polymers to be fabricated as soft, compliant structures [16,20,21]. So far, melt electrospinning has been used to process the following medical polymers: poly(ε-caprolactone) (PCL) [12,[16][17][18][21][22][23], poly(lactide-co-glycolide) [24], poly(lactic acid) [25], PCL-block-poly(ethylene glycol) [26][27][28][29][30], poly(lactide-co-caprolactone-co-acryloyl carbonate) [31], polypropylene [28,32], poly(methyl methacrylate) [33], and poly(2-ethyl-2-oxazoline) (PEtOx) [15].…”

Commercializing Electrospun Scaffolds For Pluripotent Stem Cell-Based Tissue Engineering Applications

“…Melt electrospinning produces engineered microfibers with a high degree of controllability and repeatability. Dr. Paul Dalton and his research group pioneered this technique and they have used melt electrospinning to fabricate scaffolds for a variety of tissue engineering applications [37,[83][84][85][86][87][88][89][90][91]. These applications include culturing fibroblasts and engineering replacements for damaged tendons.…”