Decoding Nano-Bio Interactions: Selective Biomolecular Recognition of Surface-Engineered Gold Nanoparticles by FXII and Plasma Coagulation Factors

We show here the utility of gold nanoparticles (AuNPs) functionalized with PEG, terminated with neutral, zwitterionic, or charged chemical groups as a versatile and homogenous platform to investigate NP–host interactions. We screened nanocoat recognition by FXII using human plasma clotting as an easy and rapid readout parameter. Distinctive procoagulant–anticoagulant patterns were found, depending not only on coat overall charge, but also on the chemical nature of charged groups and on their spatial organization. The systematic comparison of chemically fine-tuned NP coats provides a powerful tool, offering relevant insights for the rational design of nanomaterials with predictable biological behavior.