Synergistic effects of surface aminolysis and hydrolysis on improving fibroblast cell colonization within poly(L-lactide) scaffolds

This work presents a method for overcoming the low internal cell colonization within the tissue engineering scaffolds. 3D scaffolds were fabricated by the compression molding/salt leaching technique from mixtures of aminolyzed and hydrolyzed poly(L-lactide) single crystals (PLLAsc) with poly(D,L-lactide) (PDLLA) microparticles. Modified PLLAsc were used to guarantee the surface hydrophilicity, while PDLLA microparticles were used to reinforce the scaffolds. Mechanical properties, morphology, water uptake and fibroblast cell response of the scaffolds were investigated in comparison with scaffolds from only pristine, hydrolyzed, or aminolyzed PLLAsc. Results showed that the scaffolds exhibited proper morphology and hydrophilicity with an enhanced strength. Water uptake by scaffolds from modified PLLAsc was 1.9 times that from pristine PLLAsc. The scaffolds' compressive moduli increased 2.5 times by using of PDLLA (30 wt%). After cell seeding for a week, the number of cells founded on aminolyzed/hydrolyzed PLLAsc scaffolds were 4.28, 2.14, and 1.36 times that founded for pristine, aminolyzed and hydrolyzed PLLAsc scaffolds, respectively. SEM studies showed that fibroblasts migrated and spread throughout the aminolyzed/hydrolyzed PLLAsc scaffolds better than other scaffolds. Hence, combining both aminolyzed and hydrolyzed PLLAsc with PDLLA could result in a mechanically stable scaffold with an enhanced cell colonization.