(476f) Effect of Surface Chemistry on Adsorbed Solution Phase Peptide-Cation Complexes

Short peptides offer novel tools to explore the intermolecular forces that drive the process of life. Sequence design can be used to create short peptides that pinpoint and explore specific molecular motifs, to this end, I plan to highlight the specific interactions between peptide-cation complexes formed from the model tripeptide histidine-tyrosine-phenylalanine (HYF) and zinc cations with two different surface functionalized nanoparticles. The presentation will contrast how amine functionalized and carboxylic acid functionalized nanoparticles impact the morphology of the adsorbed peptide-cation complexes. Experimental techniques such as anomalous small angle x-ray scattering (ASAXS), cryogenic transmission electron microscopy (cryo-TEM), nuclear magnetic resonance (NMR), dynamic light scattering (DLS), and zeta-potential were used to show how the different surface chemistries affect not only the peptide-cation ratio but also the thickness of the surface adsorbed peptide-cation complexes. We hypothesize that the different surface functionalization results in distinct adsorption dynamics. The carboxylic acid functionalized nanoparticles show a thinner, more compact layer of the peptide-cation complexes caused by an epitaxial like growth mechanism. While the amine functionalized nanoparticles display a thicker more heterogeneous surface coverage resulting from the adsorption and stabilization of intact peptide-cation complexes.