Component-Specific Analysis of Plasma Protein Corona Formation on Gold Nanoparticles Using Multiplexed Surface Plasmon Resonance

At the nano-bio interface, human plasma differentially interacts with engineered nanomaterials through the creation of protein coronas, which in turn become primary determinants of both the pharmacokinetics and pharmacodynamics of circulating nanoparticles. Here, for the first time, the specific binding kinetics of the four major corona forming proteins (human serum albumin, fibrinogen, ApoA1, and polyclonal IgG) are determined for gold nanoparticles (AuNPs). Using a multiplexed surface plasmonic assay, highly reproducible measurements of on rate (k_on), off rate (k_off), and disassociation constant (K_D), in addition to relative amounts of protein binding, are obtained. Dramatic differences in k_on for individual components are shown as primary determinants of protein affinities, with k_on ranging over nearly two orders of magnitude for the proteins studied, while k_off remains within a factor of two for the set. The effect of polyethylene glycol (PEG) modification on plasma component binding is also studied and the effect of PEG length on human serum interaction is characterized through systematic screening of PEG molecular weight (2-30k). The effect of nanoparticle modification on particle targeting is also characterized through study of a hybrid AuNP system.