Investigation of silver nanoparticles interaction with human proteins (IgG & Fib)

Silver nanoparticles (AgNPs) have been extensively investigated and used in various areas due to their excellent antimicrobial and unique optical properties. When NPs and their derivatives encounter a physiological environment (e.g., blood, plasma, or interstitial fluid), they will be rapidly encapsulated by proteins existing in the biological fluids, which will form a type of nanoparticle called protein corona (PC). During this process, the protein type, concentration, and ratio of two proteins (IgG and Fib) were altered. The goal of this study was to understand the physicochemical reactions in the system. Dynamic light scattering (DLS) and multi-barreled light scattering (Turbiscan) were two major techniques used in this study. Our results showed that at low ionic strength, separated segments of IgG preferentially adsorbed on the surface of AgNPs and played a bridging role in increasing AgNPs aggregation. However, highly self-association Fib preferentially adsorbed and played a net capture role in decreasing the aggregation. When both proteins were present, the reverse inhibitory effect of Fib was more advantageous than the forward promoting effect of IgG. At high ionic strength, IgG and Fib could cooperate to inhibit AgNPs aggregation while Fib had a greater effect than IgG. Moreover, with a small amount of protein existing in the system, a stable PC did not form in a short time. In contrast, with a high amount of protein, a stable PC formed within 10 min. The movement of protein molecules around AgNPs corona was more vigorous when there was a higher amount of protein in the system.