Fig. 2. Morphological and biological characterization of BAM scaffolds.

(A) Degradation profiles for BAM scaffolds in PBS. By controlling the degree of polymerization and density of cross-linking in the polymer network, a zero-order kinetic profile was achieved (within the confines of the experimental conditions), resulting in approximately 50% weight loss at 12 weeks. Values are expressed as means ± SD. *P < 0.05 (significant differences between BAM60 and other tested groups). a.u., arbitrary units. (B) FTIR and (C) ¹H NMR spectra confirming the presence of the TCA metabolite succinate in the degradation solution of BAM scaffold. Absorption peaks at around 2950 cm⁻¹ (−CH₂) and 1730 cm⁻¹ (−C═O) in FTIR spectra and absorption peaks between 1.2 and 1.5 parts per million (ppm) (CH₂) in ¹H NMR spectra are attributed to succinate molecules. (D) Relative rat mesenchymal stem cell (rMSC) proliferation on BAM and PLA membrane at days 1 and 7, as determined by CCK-8. (E) F-actin staining of rMSCs on rhodamine B–stained BAM (left) and PLA (right) scaffolds. (F) F-actin staining of rMSCs on BAM membrane. Red, BAM scaffold; green, F-actin (phalloidin); blue, nuclei (4′,6-diamidino-2-phenylindole). (G) LIVE/DEAD staining for rMSCs seeded on BAM (left) and PLA (right) scaffolds and quantified using ImageJ (National Institutes of Health software). Statistical analysis: Unpaired two-tailed Student’s t test. Results in (D) represent the means ± SD of three samples.