3D poly (L-lactide)/chitosan micro/nano fibrous scaffolds functionalized with quercetin-polydopamine for enhanced osteogenic and anti-inflammatory activities

We present here a porous poly (L-lactide)/chitosan (PLLA/CS) composite scaffold with micro/nano-fiber hierarchical structure that was innovatively fabricated by combining 3D printing and thermally induced phase separation technology. Moreover, bioactive quercetin (Qu) was chosen to further functionalize the PLLA/CS scaffold with polydopamine (PDA) layer. The final results showed that the hydrophilicity and mechanical properties of the resulting PLLA/CS-D/Qu scaffold were obviously superior to those of the pure 3D printing PLLA scaffold. In vitro MC3T3-E1 cell experiments suggested that the introducing CS nanofiber network helped cells grow into the interior of the scaffold and promoted cell adhesion and proliferation. More importantly, the synergistic effect of the CS nanofiber network, PDA layer and especially sustain-released Qu, can endow the PLLA/CS-D/Qu scaffolds with not only excellent cell affinity and osteogenic activity, but also good anti-inflammatory property. Thus, the PLLA/CS-D/Qu scaffolds are expected to have good application prospects in the field of bone tissue engineering.