Synthesis and Osteoinductive Properties of Nanosized Lithium-Modified Calcium-Organic Frameworks.

The development of biomaterials that enhance bone healing and integrate with native bone tissue has gained significant interest. Metal-organic frameworks (MOFs) have emerged as promising candidates due to their unique surface properties and biocompatibility. While various bioactive element-incorporated MOFs have been studied, the osteogenic potential of lithium (Li)-modified MOFs remains largely unexplored. This study presents the synthesis and characterization of a nanosized calcium-based MOF incorporating Li⁺ ions to enhance osteoinductive properties. The MOFs were evaluated in vitro for apatite mineralization, degradation, ion release, protein adsorption, cell adhesion, viability, and osteogenic differentiation using pre-osteoblast cells. The synthesized MOFs promoted apatite formation under simulated physiological conditions, facilitated by their surface nucleation properties, controlled degradation, and sustained Li and Ca ion release. Cytocompatibility assays confirmed excellent pre-osteoblast adhesion and viability. Furthermore, CaMOF nanoparticles stimulated osteogenic differentiation by enhancing alkaline phosphatase (ALP) activity, even in the absence of osteogenic supplements. Among tested MOFs, Li/CaMOF exhibited the highest osteoinductive potential. These findings highlight lithium-modified MOFs as promising biomaterials for bone regeneration. However, further in vivo studies are necessary to assess their long-term stability, bone integration, and clinical applicability.