Microstructuring of electrospun mats employing femtosecond laser

Abstract

Electrospun mats from nano/micro-fibers with controlled porosity and pore shape may be ideal candidate for tissue engineering scaffolds. In this study three types of poly(vinyl alcohol) (PVA) mats of 41 µm-66 µm thickness with different average nano/micro-fibers diameter of 100 nm-200 nm were deposited on spunbond polypropylene (PP) filaments by electrospinning process. Controlled density porosity in the electrospun mats was introduced by Yb:KGW femtosecond laser micromachining system. The influence of electrospun mat microstructure, the distance between the adjacent laser ablation points, the number of femtosecond laser pulses on quality and structure of the laser irradiated holes were investigated. It was demonstrated that the quality of irradiated holes depends on the structure of electrospun mats (diameter of nano/micro-fibers, thickness of mats) and femtosecond laser processing parameters. Varying the distance between points of laser irradiation as well as number of applied femtosecond laser pulses it is possible to fabricate electrospun mats with increased porosity having extra pores of 22 µm-36 μm in diameter.

Dot-Matrix Hologram Rendering Algorithm and its Validation through Direct Laser Interference Patterning

“…The laser pulse picker, optical intensity attenuation, the control of interfering laser beams, and sample translation—all were implemented by employing a FemtoLab (Vilnius, Lithuania, Altechna R&D) laser workstation. More detailed information about the setup can be found in 50 , 51 . Dot-matrix hologram images were imposed by positioning the sample using XYZ translation stages (Pittsburgh, PA, USA, Aerotech) controlled via SCA software (Vilnius, Lithuania, Altechna R&D).…”

Electrospinning as a route to advanced carbon fibre materials for selected low-temperature electrochemical devices: A review

“…Similarly, these methods can be used for spinning polymers that need to remain at high temperatures throughout the electrospinning process [57][58][59], or as a means of affecting fibre morphology [60,61]. Local laser heating has also been used in-situ to heat the Taylor cone [62] or directly on the deposited fibres to alter their morphology [63,64].…”

Applications of electrospun scaffolds with enlarged pores in tissue engineering

“…42 This method not only changes the dense packing mode of conventional electrospinning fibers to enlarge the pore size, but also greatly improves the production efficiency. Different from the method mentioned above, post-electrospinning processes are the improvement and modification of the conventional electrospun scaffold, including four methods: laser-ablation, 43 ultra-sonication treatment, 44 gas foaming 45 and manual postprocessing. 46 All of these methods, based on physical principles to expand the pore size, require additional equipment.…”