Synthetic oligomers as functional modules to mimic complex adsorption mechanisms of peptide-based adhesion domains

• Applicant: Professor Dr. Hans Gerhard Börner
• Subject Area: Preparatory and Physical Chemistry of Polymers
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 442218058

The field of precision polymer chemistry provides a rapidly growing number of synthesis tools that make precision polymer segments routinely available. However, realizing functional sequences to fully exploit the capabilities of these information rich macromolecules is still at the onset. Objective of the research proposal is to synthesize and investigate precision polymer segments that mimic the excellent coating properties of a peptide-based adhesion domain for Al2O3 binding. The 12mer sequence has been recently selected by phage-display as a tyrosinase activable binder for Al2O3 surfaces. The peptide proved remarkable binding kinetics and generated coatings with high stabilities against seawater model conditions. Modern NMR spectroscopy in conjunction with computational molecular modelling provided insights on the molecular level, revealing the presence of a strong binding subdomain combined with a dynamically binding subdomain as a key to realize the excellent coating kinetics. The established design strategy, relying on the direct translation of a peptide sequence into functional sequences of precision polymer segments will be employed. By one-to-one mapping of side chain functionalities the key sequences identified for the strong binding subdomain and those for the dynamic binding subdomain will be translated into functional precision polymer sequences. Solid-phase supported synthesis applying thiolactone/Michael-chemistry will provide sequence defined oligo(amid urethane)s and controlled radical polymerization under single unit monomer insertion (SUMI) conditions will yield monodisperse oligo(acrylate)s. Sets of segments including the directly translated mother sequences and systematic sequence variations will be synthesized and investigated on film formation kinetics and coating stability. The combination of both segments (strong+dynamic) provides precision polymers that will be investigated for effective coating properties as these might mimic aspects of the complex adsorption mechanism found in the parent peptide. The comparison between the coating properties of different precision platforms allows to improve the understanding of the relevance of the sidechain functionality sequences and backbone chemistry on both, the coating kinetics and stability.Effective coating materials are essential to improve anti-corrosion, anti-fouling or adhesive applications. However, with advances in molecular understanding of oligopeptide sequence-structure-function relationships one can anticipate a broad range of sequence specific functions to be rebuilt via synthetic, non-peptidic precision polymers. Among those, material selective glues or compatibilizers for nano-interface management in composites might get possible. To realize such advanced functions, that would be difficult to be accessed by established polymers, might legitimate the synthetic efforts of precision polymer synthesis.

• DFG Programme: Research Grants
• International Connection: Australia
• Cooperation Partner: Professorin Dr. Tanja Junkers