Enhanced osteogenic differentiation of mesenchymal stem cells on metal-organic framework based on copper, zinc, and imidazole coated poly-l-lactic acid nanofiber scaffolds

The presence of inorganic bioactive minerals with polymers can accelerate and promote several processes including: bone cell joining, proliferation, differentiation, and expression of osteogenic proteins. In this study, zinc (Zn), copper (Cu), and imidazole metal-organic framework (MOF) nanoparticles were synthesized and coated over poly-l-lactic acid (PLLA) nanofibrous scaffolds for bone tissue engineering application. The surface and bioactive features of the scaffolds were characterized. The osteogenic potential of the scaffolds on human adipose tissue-derived mesenchymal stem cells (MSCs) was evaluated. Zn-Cu imidazole MOF coated PLLA scaffolds (PLLA@MOF) showed a comparable rate of MSC proliferation with the pure PLLA scaffolds and tissue culture plate (TCP). However, the PLLA@MOF potential of osteogenic differentiation was significantly greater than either pristine PLLA scaffolds or TCP. Hence, coating Zn-Cu imidazole MOF has a significant effect on the osteogenesis of MSC. Therefore, PLLA@MOF is novel scaffolds with bioactive components which are crucial for osteoconductivity and also able to provoke the osteogenesis and angiogenesis.