(201c) Ultra-Low Fouling pH-Dependent Peptide Surface Derived From Natural Amino Acids

The prevention of nonspecific biomolecule and microorganism attachment onto surfaces has many potential biomedical applications including medical implants, drug delivery carriers and biosensors. Previously, we have developed ultra-low fouling surfaces composed of peptide-based thin films that self assemble on gold surfaces. Based on the design principle of alternating positively and negatively charged residues these ?zwitterionic-like? peptides exhibit high resistance to nonspecific protein adsorption (<0.3 ng/cm² adsorbed protein), comparable to what is achieved by poly(ethylene glycol) (PEG)-based materials. Short peptides composed of the twenty naturally occurring amino acids offer an infinite number of possible combinations that can result in varying surface properties. Furthermore, peptide-based thin films are biodegradable since their final metabolized products are natural amino acids. Rational design principles were applied via simulation and experiment to identify and evaluate peptide combinations for fouling properties using surface plasmon resonance sensors. In addition to varying the peptide sequence, the fouling properties can be controlled by varying environmental factors such as pH. This talk will discuss a peptide sequence that can switch fouling properties depending on pH conditions. In addition, a brief discussion of how the peptide sequence influences the orientation and binding of peptides to gold surfaces will be included. Understanding the fundamental principles governing low fouling peptide properties can promote the development and design of more advanced materials in the future.