Micropatterning and characterization of electrospun poly(ε‐caprolactone)/gelatin nanofiber tissue scaffolds by femtosecond laser ablation for tissue engineering applications

Abstract

Experimental investigations aimed at assessing the effectiveness of femtosecond (FS) laser ablation for creating microscale features on electrospun poly(ε-caprolactone) (PCL)/gelatin nanofiber tissue scaffold capable of controlling cell distribution are described. Statistical comparisons of the fiber diameter and surface porosity on laser-machined and as-spun surface were made and results showed that laser ablation did not change the fiber surface morphology. The minimum feature size that could be created on electrospun nanofiber surfaces by direct-write ablation was measured over a range of laser pulse energies. The minimum feature size that could be created was limited only by the pore size of the scaffold surface. The chemical states of PCL/gelatin nanofiber surfaces were measured before and after FS laser machining by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS) and showed that laser machining produced no changes in the chemistry of the surface. In vitro, mouse embryonic stem cells (mES cells) were cultured on as-spun surfaces and in laser-machined microwells. Cell densities were found to be statistically indistinguishable after 1 and 2 days of growth. Additionally, confocal microscope imaging confirmed that spreading of mES cells cultured within laser-machined microwells was constrained by the cavity walls, the expected and desired function of these cavities. The geometric constraint caused statistically significant smaller density of cells in microwells after 3 days of growth. It was concluded that FS laser ablation is an effective process for microscale structuring of these electrospun nanofiber tissue scaffold surfaces.

Anisotropically oriented electrospun matrices with an imprinted periodic micropattern: a new scaffold for engineered muscle constructs

“…Importantly, this approach permits the combination of two well-known triggers of cell alignment that have usually been studied individually. Micropatterned structures have been incorporated on electrospun membranes of polyurethanes or PCL/gelatine blends using either femtosecond-pulse laser ablation (Lim et al 2011) or silicone moulds patterned with soft lithography (Dempsey et al 2010). Both methods resulted in the generation of sharp surface topographies of varying groove widths and depths of 20-500 μm, depending on the method.…”

Fabrication of Pillared PLGA Microvessel Scaffold Using Femtosecond Laser Ablation

“…Lim et al demonstrated that a femtosecond laser can be used to fabricate arbitrary patterns and pattern arrays on freestanding electrospun polycaprolactone membranes for use as functional tissue scaffolds. 29 Melissinaki et al reported the production of three-dimensional scaffolds of polylactide-based materials through layer-by-layer multiphoton polymerization. 30 Ovsianikov et al used the two-photon polymerization …”

Fabrication of pillared PLGA microvessel scaffold using femtosecond laser ablation

“…Lim et al demonstrated that a femtosecond laser can be used to fabricate arbitrary patterns and pattern arrays on freestanding electrospun polycaprolactone membranes for use as functional tissue scaffolds. 29 Melissinaki et al reported the production of three-dimensional scaffolds of polylactide-based materials through layer-by-layer multiphoton polymerization. 30 Ovsianikov et al used the two-photon polymerization method to fabricate three-dimensional computer-designed scaffolds on photosensitive methacrylamide-modified gelatin.…”