Magnetic nanoparticle formulations to activate TREK and Piezo mechanosensitive ion channels (MICA) for enhanced osteogenesis.

Magnetic nanoparticles (MNPs) have emerged as a potent tool in bone tissue engineering that utilize their intrinsic magnetism to influence the cellular microenvironment. Their capacity to boost osteoinductive, osteoconductive and angiogenic responses makes them exceptionally important for non-invasive regenerative therapies. This study presents a comparative analysis of synthesized uniform, small-sized (17-18 nm), spherical polyacrylic acid (PAA) functionalized iron oxide (IONPs) and cobalt ferrite (CFNPs) nanoparticles that were further functionalized with TREK and Piezo antibodies to precisely target these mechanosensitive ion channels. The osteogenic potential of these nanoparticles was assessed in MC3T3 and human adipose-derived stem cells under Magnetic ion channel activation (MICA) stimulation. Metabolic activity, cellular localization, ALP activity and alizarin red assay were assessed to get insights into cellular responses in osteogenesis. CFNPs exhibited comparable cellular uptake, increased metabolic activity, and elevated ALP levels relative to IONPs, especially at a low dosage of 5 µg. Alizarin red staining confirmed comparable mineralization in CFNP-treated groups under MICA stimulation compared to IONPs. Overall, these findings suggest that CFNPs, owing to high magnetic saturation, stable aqueous dispersion and a greater tendency to activate mechanosensitive ion channels than IONPs, offer a more potent platform for promoting osteogenic differentiation. This study highlights the potential for antibody-functionalized CFNPs combined with MICA as a promising non-invasive strategy for bone regeneration via mechanotransduction.