2D Covalent Organic Framework Direct Osteogenic Differentiation of Stem Cells

Area of Science:

• Materials Science
• Biomedical Engineering
• Nanotechnology

Background:

• 2D covalent organic frameworks (COFs) show promise but suffer from poor processability and instability.
• Biomedical applications are hindered by limited aqueous stability and dispersibility of existing COFs.
• Developing stable COFs is crucial for advancing their use in drug delivery and regenerative medicine.

Purpose of the Study:

• To create hydrolytically stable 2D COFs for sustained drug delivery.
• To investigate the potential of these COFs in directing stem cell fate, specifically osteogenic differentiation.
• To functionalize COFs for enhanced drug loading and release.

Main Methods:

• Boronate-based COF-5 was stabilized with Pluronic F127 (PLU) to form nanoparticles (≈25 nm thickness, ≈200 nm diameter).
• Nanoparticle internalization via clathrin-mediated endocytosis was confirmed.
• Osteogenic differentiation of human mesenchymal stem cells (hMSCs) was assessed with and without dexamethasone-loaded COFs.

Main Results:

• Fabricated stable 2D COF-PLU nanoparticles with high cytocompatibility (IC50 ≈1 mg mL⁻¹).
• Demonstrated unique induction of osteogenic differentiation in hMSCs by the 2D COFs.
• Successfully loaded and sustained the delivery of dexamethasone, further enhancing osteoinductivity.

Conclusions:

• Introduced a novel class of hydrolytically stable 2D COFs for biomedical applications.
• Established the potential of these COFs for sustained drug delivery and directing stem cell differentiation.
• Highlighted the therapeutic potential of dexamethasone-loaded COFs for bone regeneration.