Fabrication of poly (ϵ-caprolactone) microfiber scaffolds with varying topography and mechanical properties for stem cell-based tissue engineering applications

Abstract

Abstract.Highly porous poly (ε-caprolactone) microfiber scaffolds can be fabricated using electrospinning for tissue engineering applications. Melt electrospinning produces such scaffolds by direct deposition of a polymer melt instead of dissolving the polymer in a solvent as performed during solution electrospinning. The objective of this study was to investigate the significant parameters associated with the melt electrospinning process that influence fiber diameter and scaffold morphology, including processing temperature, collection distance, applied voltage and nozzle size. The mechanical properties of these microfiber scaffolds varied with microfiber diameter. Additionally, the porosity of scaffolds was determined by combining experimental data with mathematical modeling. To test the cytocompatability of these fibrous scaffolds, we seeded neural progenitors derived from murine R1 embryonic stem cell lines onto these scaffolds where they could survive, migrate, and differentiate into neurons, demonstrating the potential of these melt electrospun scaffolds for tissue engineering applications.

Using mathematical modeling to control topographical properties of poly (ε-caprolactone) melt electrospun scaffolds

“…Even though there are numerous studies on the fabrication of fibers through the use of solution electrospinning, few studies focus on controlling topographical properties of melt electrospun fibers including the uniform distribution of fiber's diameter and also the architecture of scaffolds. Hohman et al have worked on the modeling of electrospun polymeric fibers [3,29,30]. They have reported that the electrospinning jet is actually pulled along by surface stresses, electrical and elastic forces.…”

“…where, the density of the material(PCL) [3], the jet mass at time , and the charge on the jet ( ) [27] are given as :…”

“…We have previously reported that we assumed the scaffolds were cuboid shaped, composed of perfect circular cylindrical microfibers called torus [3]. In addition, scaffold porosities on flat and drum surface are calculated in the same way.…”

“…2. Mass production analogy is that measuring accumulated weight ( ) of fibers during a certain time ( ) and then spinning velocity ( 2 ) is defined by [3].…”

“…To our knowledge, there is a lack of research for linking the prominent parameters of melt electrospinning, such as applied voltage and counter electrode distance to topographical properties. In our previous study, we could successfully control the poly (є-caprolactone) (PCL) fiber diameter by varying the processing conditions such as temperature, the collecting distance, and applied high voltage between nozzle and counter electrode, and nozzle diameters [3]. PCL is tailorable in its rate of surface and bulk biodegradation, crystallinity, structure topography and mechanical properties [24].…”