Identification of Bimetallic Au/Ag Nanoparticles on lysozyme Amyloid Fibrillization and Prevent Its cytotoxicity

The accumulation of amyloid aggregates in the brain are associated with numerous neurodegenerative disorders. Several nanoparticles (NP) have been using for treatment of neurological disease. Metal nanoparticles can be modified through the construction of bimetallic architectures consisting of two distinct metals that their properties can be dramatically different from those of the corresponding single-component particles. At the present study, we evaluated the effect of the bimetallic Au/Ag nanoparticles on hen lysozyme amyloid aggregation as a model protein for amyloid formation .

In this experimental study, to induce amyloid formation, Acidic pH and high temperatures were used. Hen egg white lysozyme (HEWL) was dissolved at 2 mg/mL in 50mM glycine buffer (pH 2.5), and then incubated at 57 °C for the specified durations. The inhibitory effect of the nanoparticles against HEWL fibrillation using and ThT (thioflavin T), Congo red and MTT assay was investigated .

ThT assay showed that the particles are able to inhibit HEWL aggregation in a pattern of inverse dose-dependent inhibition and with the best inhibitory concentration 0.01 µg/ml. Kinetic study of showed that the particles caused lag phase do not change but stationary phase decreased and also cytotoxic activity of HEWL aggregates in presence of Au/Ag nanoparticleswas significantly diminished (P˂0.05) .

We anticipate that based on obtained insights in design of new bimetallic nanoparticles, rationally design of effective NP-based therapeutics for neurodegenerative diseases may be a feasible perspective .