Interfacial reinforcement in a poly-l-lactic acid/mesoporous bioactive glass scaffold via polydopamine

The weak interfacial interaction between polymer and bioceramic leads to a low reinforcing effect, even though polymer/bioceramic scaffolds are considered potential implants. In this work, a porous poly-l-lactic acid (PLLA) scaffold containing polydopamine-modified mesoporous bioactive glass (p-MBG) was fabricated by selective laser sintering. The polydopamine was introduced as a cross-linking bridge between MBG and PLLA to improve the interfacial interaction between of them. On the one hand, the amine groups of polydopamine formed strong hydrogen bonds with the hydroxyl groups of MBG. On the other hand, the catechol groups of polydopamine formed strong hydrogen bonds with the ester groups of PLLA. The PLLA/p-MBG scaffold showed higher compressive strength and modulus (62.9 MPa and 3.6 GPa, respectively) than the PLLA/MBG scaffold (41.9 MPa and 2.1 GPa, respectively). This result was explained by the fact that the enhanced interfacial adhesion promoted the dispersion of p-MBG and increased the efficiency of stress transfer in the matrix. Additionally, the PLLA/p-MBG scaffold showed good cytocompatibility. This study suggested that the PLLA/p-MBG scaffold may have a potential application in tissue engineering.