title: Affinity interactions of human immunoglobulin G with short peptides: role of ligand spacer on binding, kinetics, and mass transfer.
abstract: The interaction affinity between human IgG and a short peptide ligand (hexameric HWRGWV) was investigated by following the shifts in frequency and energy dissipation in a quartz crystal microbalance (QCM). HWRGWV was immobilized by means of poly(ethylene glycol) tethered on QCM sensors coated with silicon oxide, which enhanced the accessibility of the peptide to hIgG and also passivated the surface. Ellipsometry and ToF-SIMS were employed for surface characterization. The peptide ligand density was optimized to 0.88 chains nm(-2), which enabled the interaction of each hIgG molecule with at least one ligand. The maximum binding capacity was found to be 4.6 mg m(-2), corresponding to a monolayer of hIgG, similar to the values for chromatographic resins. Dissociation constants were lower than those obtained from resins, possibly due to overestimation of bound mass by QCM. Equilibrium thermodynamic and kinetic parameters were determined, shedding light on interfacial effects important for detection and bioseparation. Graphical Abstract The interaction affinity between human IgG and a short peptide ligand was investigated by using quartz crystal microgravimetry, ellipsometry and ToF-SIMS. Equilibrium thermodynamic and kinetics parameters were determined, shedding light on interfacial effects important for detection and bioseparation.
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695-7095, USA.|Illumina Inc., 5200 Illumina Way, San Diego, CA, 92122, USA.
authors.forename: Fei
authors.initials: F
authors.lastname: Shen
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695-7095, USA. orlando.rojas@aalto.fi.|Department of Forest Biomaterials, North Carolina State University, Raleigh, NC, 27695-8005, USA. orlando.rojas@aalto.fi.|Biobased Colloids and Materials (BiCMat), School of Chemical Technology, Aalto University, P. O. Box 16300, 00076, Aalto, Finland. orlando.rojas@aalto.fi.
authors.forename: Orlando J
authors.initials: OJ
authors.lastname: Rojas
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695-7095, USA.
authors.forename: Jan
authors.initials: J
authors.lastname: Genzer
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695-7095, USA.|ProMetic BioSciences USA, Raleigh, NC, 27695, USA.
authors.forename: Patrick V
authors.initials: PV
authors.lastname: Gurgel
authors.affiliation: Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, 27695-7095, USA.
authors.forename: Ruben G
authors.initials: RG
authors.lastname: Carbonell
mesh_terms: D000327:Adsorption; D000595:Amino Acid Sequence; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism*; D007700:Kinetics; D008024:Ligands; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D011092:Polyethylene Glycols / Q000737:chemistry; D011485:Protein Binding; D058525:Quartz Crystal Microbalance Techniques / Q000379:methods*; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D007074:Immunoglobulin G; D008024:Ligands; D010455:Peptides; D011092:Polyethylene Glycols; D012822:Silicon Dioxide
keywords: Immunoglobulin G; Peptide HWRGWV; Peptide ligands; Quartz crystal microbalance; Spacer arms