Iron oxide nanoparticles can cross plasma membranes

Area of Science:

• Biomedical Engineering
• Nanotechnology
• Materials Science

Background:

• Iron deficiency anemia is a significant global health issue.
• Conventional iron supplements have poor tolerability, leading to low compliance and ineffective treatment.
• Iron nanoformulations are being explored as a solution for food and feed fortification.

Purpose of the Study:

• To investigate the potential of iron nanoparticles (NPs) to cross plasma membranes via a non-endocytotic pathway.
• To assess the cytoplasmic uptake dynamics of different iron NPs.
• To understand the biophysical changes associated with NP membrane translocation.

Main Methods:

• Utilized a protocol to monitor cytoplasmic iron concentration changes.
• Employed electrophysiology to measure membrane conductance.
• Tested iron oxide NPs, zerovalent iron NPs, and protein-corona-coated iron oxide NPs.

Main Results:

• Iron oxide NPs, but not zerovalent iron NPs or those with a protein corona, were found to cross plasma membranes.
• A small, transient increase in membrane conductance was observed during NP membrane crossing.
• Demonstrated a novel non-endocytotic pathway for iron NP uptake into the cytoplasm.

Conclusions:

• Specific iron oxide nanoparticles can translocate across plasma membranes, offering a potential alternative to conventional iron therapies.
• The mechanism involves a transient increase in membrane conductance, suggesting a direct pore-forming or membrane-disrupting interaction.
• These findings open new avenues for developing more effective iron-deficiency anemia treatments through targeted nanoformulations.