Chaotropic Surface Arginine Correlates With Protein Corona Formation on Anti‐Fouling Biomaterial Surfaces: A Quantitative Proteomics and Protein Structure Study

ABSTRACT The protein corona determines the biocompatibility of medical devices, yet predicting its composition on anti‐fouling surfaces remains challenging. We performed quantitative proteomic analysis (nano LC‐MS/MS) of proteins adsorbed from human serum onto six model organic surfaces. Identifying over 200 proteins per surface, we found that conventional predictors, such as isoelectric point and molecular weight, failed to explain selective enrichment on non‐fouling films. Statistical analysis of surface amino acid compositions revealed that arginine uniquely distinguishes enriched from diluted proteins ( p = 0.005; Bonferroni‐corrected p = 0.125 over 25 structural descriptors, consistent with a correlation rather than a significance‐corrected effect at the α = 0.05 level). We propose, but do not yet establish causally, that surface‐exposed arginine residues, via their chaotropic guanidinium groups, may contribute to the local disruption of the protective hydration layers of anti‐fouling coatings, thereby facilitating protein accumulation through enhanced protein–surface and protein–protein interactions. These findings identify surface arginine as the leading candidate descriptor for selective adsorption on hydration‐layer–protected biomaterials and provide a hypothesis‐generating framework for the molecular basis of the Vroman effect on non‐fouling surfaces.