Processing of Polyamide Electrospun Nanofibers with Picosecond Uv-laser Irradiation

To optimize the cell colonization on electrospun polyamide nanofibers, the fiber scaffolds were processed with picosecond uv-laser irradiation. The ablation thresholds were determined in dry, wet and immersed condition. The morphology of the ablated areas was evaluated by confocal and scanning electron microscopy. It was found that the ablation thresholds of the nanofiber tissues are lower as for polyamide bulk material. While on bulk samples the ablation spot sizes are close to the focal diameter, on the fiber samples the ablation spots are more extended. Light scattering in the fiber tissue has to be taken into account. The results show that with exact setting of the laser parameters it is possible to reduce the heat-affected zone to a few micrometer. In addition, changing of the nanofiber tissue wettability by laser radiation was investigated.