Surface-modified magnetite nanoparticles affect lysozyme amyloid fibrillization

Area of Science:

• Biochemistry
• Materials Science
• Nanotechnology

Background:

• Nanoparticle (NP) surface properties significantly influence protein amyloid aggregation.
• Investigated in vitro effects of surface-modified magnetite nanoparticles (COAT-MNPs) on hen egg-white lysozyme (HEWL) amyloid fibrillization and mature fibrils.

Purpose of the Study:

• To evaluate the anti-amyloid potential of trisodium citrate (TC), gum arabic (GA), and citric acid (CA) surface-modified magnetite nanoparticles (COAT-MNPs).
• To understand how surface modifications impact nanoparticle interactions with amyloidogenic proteins.

Main Methods:

• Physico-chemical characterization using Dynamic Light Scattering (DLS).
• Amyloid inhibition and fibril destruction assessed via Thioflavin T (ThT) and tryptophan (Trp) fluorescence assays.
• Morphological analysis using Atomic Force Microscopy (AFM) and Gwyddion software; cytotoxicity evaluated by Trypan Blue (TB) assay.

Main Results:

• Surface modification agents alter COAT-MNP properties and anti-amyloid efficacy.
• COAT-MNPs inhibit fibrillization by interacting with early protein aggregates (nuclei and oligomers).
• COAT-MNPs can disrupt mature amyloid fibrils by interacting with hydrophobic residues, destabilizing beta-sheet structures.

Conclusions:

• COAT-MNPs effectively inhibit HEWL fibrillization and degrade mature fibrils.
• Trisodium citrate-modified nanoparticles (TC-MNPs) demonstrated the highest potency among the tested COAT-MNPs.
• Nanoparticle surface engineering is a viable strategy to modulate protein amyloid aggregation.