2.3.2. MTS Proliferation Assay

Proliferation was assessed after 1, 3, and 7 days of fibroblast culture. After each time point, the culture medium was removed, and meshes were transferred to the new 24-well plate. Then, 80 μL of MTS reagent and 400 μL of cell culture medium were added, and assay was proceeded as described above. For proliferation assessment with SEM, after the defined time of 1, 3, and 7 days, cell culture samples were transferred to the new 24-well plate and rinsed 3 times with PBS. Next, they were fixed with a 2.5% formaldehyde solution for 2 h at 4 ◦C. The solution was removed and the samples were again rinsed with PBS solution, then dehydrated using a series of ethanol solutions with the concentrations: 50%, 70%, 96%, and 99.9%. The meshes were left to dry under the hood. Before the SEM observation, the samples were coated with a 5 nm layer of Au.

#### 2.3.3. Statistical Analyses

The statistical analyses were performed using OriginPro (v2019 SR2, OriginLab, USA). Analysis of variance (ANOVA) with a Tukey test was performed with significance at p < 0.02. For fiber diameter and contact angle measurement, errors are based on standard deviation calculation.
