Specific Adhesion of Peptides on Semiconductor Surfaces in Experiment and Simulation

We report on self-assembly, clustering, and conformational phases of peptides on inorganic semiconductor surfaces. The peptide-covered surface fraction can differ by a factor of 25, depending mainly on surface and peptide polarity. Low adhesion induces large and soft clusters, which also have high contact angles to the surface. Direct surface adhesion of a peptide molecule competes with forming molecular aggregates which offer an overall reduced surface contact. Simulating a simple hybrid model yields a pseudophase diagram with a rich, temperature and solvent-quality dependent variety of subphases which are specific to the hydrophobicity and polarity of the considered substrates.