Luer lock

Aqueous polymer solutions were prepared by dissolving 5% (w/w) PEO in boiling water with continuous stirring. The samples were cooled down to room temperature and stirred overnight at 23 °C by magnetic stirring until homogenous solutions were obtained. Finally, sodium chlorite 20% (w/w) aqueous solution was added to the PEO solution to reach a concentration of 0.1% (w/w). Control PEO samples without active ingredients were prepared accordingly. Nanofiber production was carried out on lab-scale electrospinning equipment (SpinSplit Ltd., Budapest, Hungary). Precursor solutions were placed into plastic syringes (Luer lock, Sigma-Aldrich Ltd., Budapest, Hungary) with a volume of 3 mL and mounted to the pumping system of the instrument. The syringes were connected to a 22-gauge needle through Teflon tubes. The feeding rate for PEO control samples was 0.08 µL/s, with an applied voltage of 10.5 kV. The NaClO₂-loaded PEO samples were prepared with a 0.07 µL/s feeding rate and 14.8 kV of applied voltage. The samples were collected on aluminum foil, and the needle-collector distance was set to 21.5 cm. The experiments were performed in a well-controlled room, the temperature was set to 23 ± 1 °C and the relative humidity was 25 ± 5% (Figure 1).