BPS2026 – Computational evaluation of polystyrene-binding polypeptides

Micro- and nanoplastic wastes pose significant environmental and health concerns due to increased likelihood of their consumption as they break down from larger plastic waste. Freshwater is highly contaminated with these plastics, as current water filtration methods are ineffective at the nanoscale. To address this issue, new materials and methods are needed to capture and remove nanoplastics from water. Peptide-based materials are ideal due to their ability to perform functions with highly specific molecular recognition. However, the vast design space of amino acid sequences necessitates computational methods for screening and identifying peptide sequences capable of selective binding to target plastics. Furthermore, an evaluatory method is needed to determine if a given plastic binding peptide is effective for a target plastic. We approach these challenges by using molecular dynamics simulations with enhanced sampling methods to determine if a candidate peptide sequence can be used to capture nanoscale polystyrene. With the addition of free-energy calculations and analysis of binding configurations, we present a thermodynamic understanding of successful polystyrene capture with solvation analysis that can inform optimized design of nanoplastic-sequestering materials.