Micro Versus Macro - The Effect of Environmental Confinement on Cellular Nanoparticle Uptake

Area of Science:

• Biomedical Engineering
• Cell Biology
• Nanotechnology

Background:

• Cellular microenvironments influence cell behavior, including metabolism, growth, and endoplasmic reticulum stress.
• The effect of the microenvironment on nanoparticle uptake remains largely unexplored.
• Understanding nanoparticle uptake is crucial for drug delivery and nanomedicine.

Purpose of the Study:

• To investigate the influence of microenvironment on nanoparticle uptake by cells.
• To compare nanoparticle uptake in cells cultured in a macroenvironment (petri dish) versus a microenvironment (microfluidic channel).

Main Methods:

• Utilized J774 murine macrophages and fluorescent nanodiamonds (FND) as a model system.
• Cultured equal numbers of cells in petri dishes and microfluidic channels.
• Quantified FND uptake via imaging after incubation, fixation, and staining.

Main Results:

• Significantly higher FND uptake was observed in cells cultured in petri dishes compared to microfluidic chips.
• Environmental factors such as CO2 levels, medium pH, and surface area-to-volume ratio in microfluidic systems may explain the reduced uptake.
• This suggests microenvironmental conditions critically affect cellular nanoparticle interactions.

Conclusions:

• The cellular microenvironment plays a significant role in modulating nanoparticle uptake efficiency.
• Differences in CO2, pH, and surface area-to-volume ratio within microfluidic devices lead to lower nanoparticle uptake compared to traditional petri dishes.
• These findings have implications for designing in vitro models and optimizing nanoparticle-based therapies.