Cylindrical scaffold samples with a height of 3 mm and a diameter of 5 mm were examined under a stereo microscope (SM33, Hund Wetzlar, Wetzlar, Germany) and documented with a Nikon camera (DS-2Mv) using the NIS-Elements software (Nikon, Duesseldorf, Germany).
High-resolution pictures were taken via SEM. To this end scaffold disks with a thickness of 0.5 to 1 mm were applied to a sample holder using Conductive Carbon Cement (Leit-C, Plano, Wetzlar, Germany) and coated with gold (Sputter coater MED 020, Bal-Tec, Leica Microsystems, Wetzlar, Germany). Images were recorded on a CS 44 scanning electron microscope (Cam Scan, Cambridgeshire, United Kingdom) with the Noran System Six software (version 1.8).
Scanning electron microscopy of hMSC on the scaffolds was carried out using a Zeiss DSM 982 Gemini FESEM (Oberkochen, Germany) to assess cell morphology. For sample preparation, hMSC were seeded on coated scaffolds and cultivated for 3 days. Subsequently, cells were fixed with 4% paraformaldehyde and dehydrated using a graded ethanol series followed by infiltration with hexamethyldisilazane (Fluka, Germany). Samples were then mounted on stubs and coated with carbon in a Bal-Tec SCD 050 coater (Bal-Tec AG, Liechtenstein). Microscopy was performed in HiVac mode at an acceleration voltage of 3 kV using the SE-Inlens detector.
High-resolution pictures were taken via SEM. To this end scaffold disks with a thickness of 0.5 to 1 mm were applied to a sample holder using Conductive Carbon Cement (Leit-C, Plano, Wetzlar, Germany) and coated with gold (Sputter coater MED 020, Bal-Tec, Leica Microsystems, Wetzlar, Germany). Images were recorded on a CS 44 scanning electron microscope (Cam Scan, Cambridgeshire, United Kingdom) with the Noran System Six software (version 1.8).
Scanning electron microscopy of hMSC on the scaffolds was carried out using a Zeiss DSM 982 Gemini FESEM (Oberkochen, Germany) to assess cell morphology. For sample preparation, hMSC were seeded on coated scaffolds and cultivated for 3 days. Subsequently, cells were fixed with 4% paraformaldehyde and dehydrated using a graded ethanol series followed by infiltration with hexamethyldisilazane (Fluka, Germany). Samples were then mounted on stubs and coated with carbon in a Bal-Tec SCD 050 coater (Bal-Tec AG, Liechtenstein). Microscopy was performed in HiVac mode at an acceleration voltage of 3 kV using the SE-Inlens detector.