Bioinspired Chiral Nanocrystals For Bone Regeneration

To investigate the osteogenic potential and underlying molecular mechanisms of chiral cellulose nanocrystals (CNC). Fabrication of chiral CNC films by controlling self-assembly to induce chiral structures; Characterization of chirality using circular dichroism (CD) spectroscopy; Biocompatibility assessment via Live/Dead staining and CCK-8 assays (cytotoxicity and proliferation); Osteogenic gene expression analysis by qPCR (BMP2, BSP, OCN, OSX); Osteogenic activity evaluation through ALP staining. The chiral-structured cellulose nanocrystal (CNC) material exhibited no cytotoxicity toward pre-osteoblasts, while significantly promoting their proliferation and osteogenic differentiation. CNC spectroscopy confirmed the presence of left-handed cholesteric liquid crystalline structures in all films, as evidenced by selective reflection of left-handed circularly polarized light. Live/Dead staining demonstrated that achiral CNC exhibited higher cytotoxicity, resulting in poor cell growth, whereas chiral CNC groups showed improved cell viability and normal morphology compared to the control. CCK-8 assay further revealed that all tested materials promoted cell proliferation to varying degrees. qPCR analysis indicated significant upregulation of osteogenic markers (BMP2, BSP, OCN, OSX), with CNC2 displaying the strongest pro-osteogenic potential among all groups. ALP activity assay consistently demonstrated that CNC1 and CNC2 exhibited superior osteogenic induction capacity. Therefore, the chiral-structured CNC demonstrates favorable architectural properties and significant osteoinductive potential in vitro.