Nanoparticle geometry and surface orientation influence mode of cellular uptake

Area of Science:

• Nanomaterial science
• Cell biology
• Toxicology

Background:

• Engineering safer nanomaterials requires understanding cellular uptake and intracellular fate.
• Nanoparticle geometry is a critical factor influencing these interactions.

Purpose of the Study:

• To determine silica nanoparticle geometry's role in cellular uptake and transport.
• To evaluate the impact of nanoparticle shape on cellular viability and endocytic pathways.

Main Methods:

• Utilized various silica nanoparticle geometries with primary and immortalized macrophages and epithelial cells.
• Assessed cellular viability and toxicity.
• Screened chemical inhibitors of endocytosis to elucidate uptake mechanisms.
• Analyzed time-dependent uptake patterns and nanoparticle orientation effects.

Main Results:

• Observed significant differences in macrophage viability based on phenotype; epithelial cells showed no toxicity.
• Demonstrated distinct time-dependent uptake patterns for different nanoparticle geometries across all cell lines.
• Identified varied endocytic pathways for different geometries, potentially linked to nanoparticle orientation.
• Found evidence that uptake patterns initiate distinct downstream cellular pathways.

Conclusions:

• Nanoparticle geometry significantly influences cellular uptake, transport, and intracellular fate.
• Particle orientation at the cell surface may dictate uptake mechanisms and subsequent cellular responses.
• These findings are crucial for the rational design of safer nanomaterials with predictable biological interactions.