pH-Mediated Mucus Penetration of Zwitterionic Polydopamine-Modified Silica Nanoparticles

Area of Science:

• Biomaterials Science
• Nanotechnology
• Polymer Chemistry

Background:

• Zwitterionic polymers are excellent trans-mucus nanocarriers due to their antifouling properties.
• The influence of pH on the mucus penetration of pH-sensitive zwitterionic polymers is not well understood.

Purpose of the Study:

• To investigate the pH-mediated mucus penetration behavior of zwitterionic polydopamine-modified silica nanoparticles (SiNPs-PDA).
• To explore the interactions between SiNPs-PDA and mucin across different pH values.

Main Methods:

• Preparation of zwitterionic SiNPs-PDA with a specific isoelectric point.
• Multiple-particle tracking to analyze nanoparticle diffusion in mucus at various pH levels.
• Biophysical analysis to determine the interaction mechanisms between nanoparticles and mucin.

Main Results:

• SiNPs-PDA diffusion in mucus was significantly faster at pH 5.6 compared to pH 3.0 or 7.0.
• Trans-mucus behavior was influenced by hydrophobic, electrostatic, and hydrogen bonding interactions between mucin and nanoparticles.
• In vivo distribution studies confirmed pH-mediated mucus penetration in the stomach, intestine, and lung.

Conclusions:

• Zwitterionic nanomaterials exhibit pH-dependent mucus penetration capabilities.
• Understanding these pH-mediated interactions is crucial for designing advanced zwitterionic nanocarriers for diverse physiological environments.