Cells have the ability to break and chemically modify GaP(As) nanowires

Area of Science:

• Biophysics
• Materials Science
• Nanotechnology

Background:

• Semiconductor nanowires possess unique electronic and optical properties due to their geometry.
• Vertical nanowire substrates offer non-uniform surfaces ideal for studying cell-wire interactions.
• Previous studies on cells cultured on nanowires left questions about cell rupture and interaction mechanisms unanswered.

Purpose of the Study:

• To investigate the interaction between semiconductor nanowires and cell membranes.
• To explore the fate and effects of nanowires internalized by cells.
• To assess the potential of these interactions for developing novel biointerfaces and intracellular visualization techniques.

Main Methods:

• Culturing cells on semiconductor nanowire substrates.
• Observing nanowire-cell membrane penetration and internalization using microscopy.
• Assessing cell viability and intracellular processes post-nanowire uptake.
• Analyzing changes in nanowire luminescence spectra.
• Measuring forces generated by cells during nanowire breakdown.

Main Results:

• Nanowires were observed to penetrate cell membranes, be broken by cells, and become trapped intracellularly.
• Cells remained viable for up to 7 days after nanowire internalization and mechanical poration.
• Internalized nanowires were aligned near the nucleus and expelled via pseudopodia, forming nanowire-rich fibrils.
• Nanowire endocytosis led to chemical modification, evidenced by a red shift in luminescence spectra.
• Cells generated forces up to several hundred nanoNewtons to break down nanowires.

Conclusions:

• Cellular uptake of semiconductor nanowires involves complex intracellular processes including penetration, internalization, and expulsion.
• Nanowire-cell interactions can lead to cellular viability and significant alterations in nanowire properties.
• These findings highlight the potential of nanowire-cell interactions for advanced intracellular visualization and biointerface development.