Protein–Polymer Interaction Characteristics Unique to Nanoscale Interfaces: A Perspective on Recent Insights

Abstract

Protein interactions at polymer interfaces represent a complex but ubiquitous phenomenon that demands an entirely different focus of investigation than what has been attempted before. With the advancement of nanoscience and nanotechnology, the nature of polymer materials interfacing proteins has evolved to exhibit greater chemical intricacy and smaller physical dimensions. Existing knowledge built from studying the interaction of macroscopic, chemically alike surfaces with an ensemble of protein molecules cannot be simply carried over to nanoscale protein− polymer interactions. In this Perspective, novel protein interaction phenomena driven by the presence of nanoscale polymer interfaces are discussed. Being able to discern discrete protein interaction events via simple visualization was crucial to attaining the much needed, direct experimental evidence of protein−polymer interactions at the single biomolecule level. Spatial and temporal tracking of particular proteins at specific polymer interfaces was made possible by resolving individual proteins simultaneously with those polymer nanodomains responsible for the protein interactions. Therefore, such single biomolecule level approaches taken to examine protein−polymer interaction mark a big departure from the mainstream approaches of collecting indirectly observed, ensembleaveraged protein signals on chemically simple substrates. Spearheading research efforts so far has led to inspiring initial discoveries of protein interaction mechanisms and kinetics that are entirely unique to nanoscale polymer systems. They include protein selfassembly/packing characteristics, protein−polymer interaction mechanisms/kinetics, and various protein functionalities on polymer nanoconstructs. The promising beginning and future of nanoscale protein−polymer research endeavors are presented in this article.

Examining polymer‐protein biophysical interactions with small‐angle x‐ray scattering and quartz crystal microbalance with dissipation

“…While QCMD data can also be used to confirm the formation of complexes and the kinetics of complexation, SAXS data provides additional information about the conformation of the complexes. The results we have obtained will also be useful in addressing a broader question of the structural changes that occur in proteins at polymer interfaces 58,60 …”

“…The results we have obtained will also be useful in addressing a broader question of the structural changes that occur in proteins at polymer interfaces. 58,60 Our preliminary work with covalently immobilized enzymes provided justification for conducting adsorption experiments directly on gold sensors (Figure S1). Experiments at different HRP concentrations was useful in selecting the appropriate concentration of HRP (Figure 2).…”

“…The results we have obtained will also be useful in addressing a broader question of the structural changes that occur in proteins at polymer interfaces. 58 , 60 …”

Protein-Based Hydrogels: Promising Materials for Tissue Engineering

“…The most important goal of the chemical cross-linking technique is the 3D networkstructure PBH's production through the formation of resistant and solid covalent bonds within its network [34,61]. The covalent cross-linking of target residues and particular chains on proteins [62][63][64], chemical coupling [19,65], and click reactions [66][67][68] are some of the chemical cross-linking approaches that have been reported.…”

Distinctive Adsorption Mechanism and Kinetics of Immunoglobulin G on a Nanoscale Polymer Surface

“…We have made research efforts in this regard. ,,− For example, we have shown that globular proteins such as immunoglobulin G (IgG), serum albumin (SA), and horseradish peroxidase (HRP) exclusively adsorb onto the polystyrene (PS) nanodomain regions, leaving the neighboring poly­(methyl methacrylate) (PMMA) nanodomain areas completely free of proteins on the BCP surface of PS- block -PMMA (PS- b -PMMA). ,,, The highly selective adsorption of the globular proteins to PS over PMMA observed on the nanoscale BCP surface is distinct from their behaviors onto chemically homogeneous, bulk, or macroscopic scale polymer surfaces. , For example, when homopolymer surfaces of PS and PMMA were used instead, the proteins were found to adsorb not only on PS but also on PMMA …”