Membrane monolayer protrusion mediates a new nanoparticle wrapping pathway

Area of Science:

• Biophysics
• Nanotechnology
• Cell Biology

Background:

• Nanoparticle (NP) interactions with lipid membranes are crucial for biomedical applications and understanding cytotoxicity.
• Conventional cellular uptake mechanisms like endocytosis do not fully explain all NP-membrane interactions.

Purpose of the Study:

• To investigate novel pathways of nanoparticle internalization into lipid membranes.
• To elucidate the mechanisms underlying NP wrapping by membranes.

Main Methods:

• Computer simulations were employed to model NP-lipid membrane interactions.
• Free energy analysis was used to support simulation findings.

Main Results:

• A novel NP wrapping pathway, distinct from endocytosis, was identified.
• This pathway is regulated by membrane monolayer protrusion under conditions of strong NP-membrane adhesion and low membrane tension.
• NP internalization can be facilitated by decreasing membrane tension, breaking membrane symmetry, or applying external force.

Conclusions:

• Nanoparticles can internalize via a unique membrane wrapping mechanism mediated by monolayer protrusion.
• This discovery offers new insights into nanoparticle-cell interactions and potential therapeutic delivery strategies.