Hemolysis Testing

The hemolysis rate was evaluated by measuring the concentration of hemoglobin released into the solution phase from erythrocytes in diluted whole blood exposed to the electrospun nanofibers. The samples on coverslips were individually placed into 24-well plates and immersed in 2 mL PBS at 37 °C for 30 min. The negative control groups contained only 2 mL of PBS, while positive control groups were comprised of 2 mL deionized water for the aim of inducing maximal lysis of erythrocytes (n = 3 for each testing group). Then, 40 μL of aforementioned anticoagulated fresh whole blood was added into each well and incubated for 60 min at 37 °C, after which the suspensions were removed into centrifuge tubes and centrifuged at 100× g for 5 min. The supernatants were subjected to measure the absorbance at 570 nm using a microplate reader (SynergyH1/H1M, BioTek, China).