title: Correlating single-molecule and ensemble-average measurements of peptide adsorption onto different inorganic materials.
abstract: The coating of solid-binding peptides (SBPs) on inorganic material surfaces holds significant potential for improved surface functionalization at nano-bio interfaces. In most related studies, the goal has been to engineer peptides with selective and high binding affinity for a target material. The role of the material substrate itself in modulating the adsorption behavior of a peptide molecule remains less explored and there are few studies that compare the interaction of one peptide with different inorganic substrates. Herein, using a combination of two experimental techniques, we investigated the adsorption of a 16 amino acid-long random coil peptide to various inorganic substrates - gold, silicon oxide, titanium oxide and aluminum oxide. Quartz crystal microbalance-dissipation (QCM-D) experiments were performed in order to measure the peptide binding affinity for inorganic solid supports at the ensemble average level, and atomic force microscopy (AFM) experiments were conducted in order to determine the adhesion force of a single peptide molecule. A positive trend was observed between the total mass uptake of attached peptide and the single-molecule adhesion force on each substrate. Peptide affinity for gold was appreciably greater than for the oxide substrates. Collectively, the results obtained in this study offer insight into the ways in which inorganic materials can differentially influence and modulate the adhesion of SBPs.
authors.affiliation: School of Materials Science and Engineering and Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive 637553, Singapore. njcho@ntu.edu.sg.
authors.forename: Seong-Oh
authors.initials: SO
authors.lastname: Kim
authors.forename: Joshua A
authors.initials: JA
authors.lastname: Jackman
authors.forename: Masahito
authors.initials: M
authors.lastname: Mochizuki
authors.forename: Bo Kyeong
authors.initials: BK
authors.lastname: Yoon
authors.forename: Tomohiro
authors.initials: T
authors.lastname: Hayashi
authors.forename: Nam-Joon
authors.initials: NJ
authors.lastname: Cho
mesh_terms: D000327:Adsorption; D000537:Aluminum Oxide / Q000737:chemistry; D000595:Amino Acid Sequence; D006046:Gold / Q000737:chemistry; D007287:Inorganic Chemicals / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D058525:Quartz Crystal Microbalance Techniques; D012825:Silicon / Q000737:chemistry; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry
chemical_list: D007287:Inorganic Chemicals; D010455:Peptides; C009495:titanium dioxide; D006046:Gold; D014025:Titanium; D000537:Aluminum Oxide; D012825:Silicon