Peptide Corona Formation on Polyethylene Surfaces: A Combined Computational and Experimental Study

Plastics, now integral to daily life, have entered the ecosystem by forming ecocoronas with biological and nonbiological molecules. Proteins, which are highly abundant in these systems, act as efficient partners for plastics to blend into their surroundings, governed by the chemical properties of amino acids and the surface potential of plastics. This study employs molecular modeling to investigate the interactions between polyethylene nanoplastics and amino acids. It also provides a modeling protocol for studying corona formation at the atomic level. Plastic nanoparticles are generated using simulated annealing and molecular dynamics simulations, followed by the formation of plastic-peptide coronas. This integrated computational-experimental approach reveals, for the first time, distinct sequence-dependent adsorption behaviors where valine-, tyrosine-, and tryptophan-based peptides form compact, high-affinity coronas, whereas arginine-based peptides exhibit weak, dispersed adsorption with greater solvent exposure. The valine-based corona demonstrates aggregation, whereas the arginine-based corona destabilizes at elevated temperatures. Computational predictions are quantitatively validated by equilibrium adsorption isotherms, providing confidence in the simulation framework. The complexation with plastic nanoparticles affects the backbone dihedral angles and, consequently, the secondary structure of the peptides. These findings provide atomistic insight into the plastic-peptide corona formation and establish a mechanistic foundation for predicting peptide-plastic interactions, with implications for environmental persistence, biomolecular recognition, and the design of polymeric materials with controlled biointerface properties.