Microfibers of polylactic acid with polypyrrole particles with ultrahydrophobic surface

This work presents the formation of hybrid electrospun fibers of polylactic acid (PLA) with plasma synthesized polypyrrole (PPy) particles inside with the objective to prepare fibers with controlled hydrophobicity for biomedical applications. Krebs–Ringer and phosphate-buffered saline solutions were used to test the fibers. The obtained PPy particles had diameter in the 60–1000 nm range and were suspended in PLA-chloroform solutions with a PPy/PLA = 0.027 mass ratio. Hybrid electrospun microfibers were prepared with this suspension with diameters in the 0.12–9.0 µm range. Contact angles were measured on the fibers with the test solutions in the 113°–147° interval, most of them in the ultrahydrophobic (120°–150°) region. The lowest angles were obtained with particles synthesized at 20 W and the highest with particles synthesized at 100 W. The angle difference, up to 15°, was correlated with resonant ≈C≈ groups of the particles through the fiber ultraviolet absorption. Graphical abstract