Product Code: ICAL06_M203

Femtosecond Laser Structuring of PCL and PET Electrospun Nanofiber Mesh
Authors:
Hae Woon Choi, Ohio State University; Columbus OH USA
Jed Johnson, Ohio State University; Columbus OH USA
Dave F Farson, Ohio State University; Columbus OH USA
John Lannutti, Ohio State University; Columbus OH USA
Presented at ICALEO 2006

Femtosecond laser machining of electrospun poly-caprolactone (PCL) and polyethylene terephthalate (PET) nanofiber meshes is studied. Structured meshes are needed to promote and control cell growth in tissue scaffold applications. Femtosecond laser radiation with fundamental (775nm) and SHG (338nm) wavelengths was effectively used to fabricate micron-size channels on both PCL and PET. Focus spot size and pulse energy were varied to determine the affects on the channel size and the characteristics of the nanofibers on the edges of single-pass and multiple-pass channels. The femtosecond laser was found to be effective for structuring the surface of the polymer meshes, resulting in much more uniform ablated patterns and less fiber melting compared to Q-switched laser ablation. Channels with widths ranging from 20 um to 250 um and depths ranging from 75 um to 250 um were produced. Some melting of fibers was observed on the edges of the ablated channels. It was found the squared ablation diameter versus fluence relationship for the PCL mesh was non-logarithmic so the ablation threshold for the material could not be estimated. This was attributed to thermal affects due to radiation from a plasma formed below the surface level of the mesh during channel ablation. Mouse embryo stem cells were cultured to evaluate the functionality of the structures.