Unraveling the Mechanism and Kinetics of Binding of an LCI‐eGFP‐Polymer for Antifouling Coatings

Abstract

The ability of proteins to adsorb irreversibly onto surfaces opens new possibilities to functionalize biological interfaces. Herein, the mechanism and kinetics of adsorption of protein‐polymer macromolecules with the ability to equip surfaces with antifouling properties are investigated. These macromolecules consist of the liquid chromatography peak I peptide from which antifouling polymer brushes are grafted using single electron transfer‐living radical polymerization. Surface plasmon resonance spectroscopy reveals an adsorption mechanism that follows a Langmuir‐type of binding with a strong binding affinity to gold. X‐ray reflectivity supports this by proving that the binding occurs exclusively by the peptide. However, the lateral organization at the surface is directed by the cylindrical eGFP. The antifouling functionality of the unimolecular coatings is confirmed by contact with blood plasma. All coatings reduce the fouling from blood plasma by 8894% with only minor effect of the degree of polymerization for the studied range (DP between 101 and 932). The excellent antifouling properties, combined with the ease of polymerization and the straightforward coating procedure make this a very promising antifouling concept for a multiplicity of applications.

Kill&Repel Coatings: The Marriage of Antifouling and Bactericidal Properties to Mitigate and Treat Wound Infections

“…This indicates that the adsorption process is mediated by the binding of the same moiety, LCI, in agreement with previous reports from our group. [ 15 ] Thus, the ratio of LCI‐EndLys to LCI‐eGFP‐Polymer at the surface will be identical to the one in solution.…”

“…In the presence of a surface, the protein changes its molecular conformation to maximize weak interactions and lower the interfacial energy, resulting in its irreversible adsorption while segregating the polymeric part of the molecule away from the surface, leading to an oriented type of immobilization. [ 15 ] This oriented adsorption of the hybrids by the protein leaves a brush‐like coating on the periphery of the surface that exhibits antifouling properties on par with the best polymer brushes but lacks bactericidal properties.…”

Tackling the Root Cause of Surface‐Induced Coagulation: Inhibition of FXII Activation to Mitigate Coagulation Propagation and Prevent Clotting

“…However, translation of the antifouling polymer brushes to real devices might be challenging due to complex polymerization conditions. Therefore, future work could focus on the combination of the modulatory level with brush-like alternatives, e.g., ultrathin surface-attached hydrogels, [52] polymer-peptidehybrids, [53][54][55] as well as other oligomeric, [47] polymeric, [56,57] or plasma-deposited [58] initiators for grafting from polymer substrates.…”

Brush‐Like Coatings Provide a Cloak of Invisibility to Titanium Implants

“…In the presence of a surface, the protein drives the adsorption of the hybrid to the surface, causing the polymeric segment to orient away from the surface and form a brush-like interface. [26] This one-molecule-thick coating (4-6 nm) showed outstanding resistance to protein fouling on par with the best antifouling polymer brushes in spite of its much lower thickness. [26,27] Ultrathin surface-attached hydrogels as an alternative for antifouling polymer brushes were developed by Rühe et al [29] The use of comonomers that can be thermally or photo-chemically activated enabled the modification of polymeric surfaces with hydrophilic polymers.…”

“…To overcome these shortcomings, our group has recently developed several strategies to form brush-like coatings on polymeric surfaces with a high potential for clinical application. These strategies are based on protein-polymer hybrids (LCI-eGFP-Polymer) [25][26][27] and ultrathin surface-attached hydrogels [28] containing hydrophilic polymers of N-(2-hydroxypropyl) methacrylamide (HPMA) and carboxybetaine methacrylamide (CBMAA), which have demonstrated unsurpassed repellency as polymer brushes. The protein-polymer hybrids consist of a surface affine fusion protein and an antifouling polymer block dissolved in water.…”