Laser-perforated polymer films for possible use in tissue engineering

Ablation experiments were carried out to modify surfaces of poly(3-hydroxybutyrate) (PHB), poly(lactic acid) (PLA), poly(methyl methacrylate) (PMMA), and polyurethane (PU)/poly(dimethylsiloxane) (PDMS) films using a krypton fluoride excimer laser, which was employed to produce cavities and orderly perforated holes on the films for tissue engineering. Surface patterning was assisted by prefabricated stainless steel masks with different mesh sizes. Film surfaces modified in this manner were studied and analyzed for different laser parameters (such as pulse energy and pulse repetition rate), and characterized using optical microscopy and surface profilometry. The present study demonstrated that laser surface modification of PHB, PLA, PMMA, and PU/PDMS films can be achieved with a high degree of success and precision. The effect of the surface changes on the tendency of cells to adhere to the polymers, as well as its effect on cell growth, were subsequently investigated. Cell–polymer film interfacial interactions were examined based on the proliferation of human fibroblast cells cultured on the laser-modified membranes in comparison to unexposed membranes and tissue culture dishes as controls. Surface topographical features created by excimer laser modification seem to improve the attachment and growth of human fibroblast cells on some of the films.