Tailoring Pseudo-Zwitterionic Bifunctionalized Silica Nanoparticles: From Colloidal Stability to Biological...

Area of Science:

• Biomaterials Science
• Nanotechnology
• Surface Chemistry

Background:

• Zwitterionic molecules are excellent for resisting protein adsorption, offering an alternative to polyethylene glycol.
• Zwitterionic-like nanoparticles, created by coimmobilizing positive and negative ligands, prevent protein corona formation and allow bioconjugation.

Purpose of the Study:

• To evaluate the stability and hemocompatibility of zwitterionic-like silica nanoparticles in biological environments.
• To determine if electrostatic neutrality is adequate for achieving low-fouling and stealth properties in physiological conditions.

Main Methods:

• Synthesized zwitterionic-like silica nanoparticles using varying ratios of THPMP and DETAPTMS organosilanes.
• Investigated nanoparticle behavior, including protein adsorption and colloidal stability, in realistic biological milieus.
• Assessed hemocompatibility through red blood cell disruption assays.

Main Results:

• The optimized zwitterionic-like nanoparticles resisted single-protein adsorption.
• Significant loss of colloidal stability was observed upon interaction with diverse serum proteins.
• The nanoparticles exhibited poor hemocompatibility, leading to substantial red blood cell damage.

Conclusions:

• Zwitterionic-like nanoparticles demonstrate limited effectiveness in complex biological fluids, failing to maintain colloidal stability against serum proteins.
• Exposure of ionic groups facilitates environmental interactions, suggesting that electrostatic neutrality alone is insufficient for robust low-fouling and stealth characteristics.
• Further research is needed to develop nanoparticles with improved biocompatibility and stability for clinical applications.