Adsorption Kinetics of an Engineered Gold Binding Peptide by Surface Plasmon Resonance Spectroscopy and a Quartz Crystal Microbalance

• Published in: Langmuir Vol. 22; no. 18; pp. 7712 - 7718
• Main Authors: Tamerler, Candan, Oren, Ersin Emre, Duman, Memed, Venkatasubramanian, Eswaranand, Sarikaya, Mehmet
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 29.08.2006
• Subjects: Adsorption; Amino Acid Sequence; Chemistry; Crystallization; Exact sciences and technology; General and physical chemistry; Gold - chemistry; Hydrogen-Ion Concentration; Kinetics; Microscopy, Atomic Force; Molecular Sequence Data; Peptides - chemistry; Quartz - chemistry; Surface physical chemistry; Surface Plasmon Resonance; Surface Properties; Binding; Self assembly; Monolayer; Gold; Stability; Peptides; Crystals; Transition metal; Potential; Topology; Surface plasmon; Surface effect; Substrate; Kinetic model; Adsorption; Aminoacid; Binding energy; Thermodynamic parameter; Environment; Resonance; Kinetics; Kinetic parameter; Quartz microbalance
• ISSN: 0743-7463; 1520-5827
• DOI: 10.1021/la0606897

The adsorption kinetics of an engineered gold binding peptide on gold surface was studied by using both quartz crystal microbalance (QCM) and surface plasmon resonance (SPR) spectroscopy systems. The gold binding peptide was originally selected as a 14-amino acid sequence by cell surface display and then engineered to have a 3-repeat form (3R-GBP1) with improved binding characteristics. Both sets of adsorption data for 3R-GBP1 were fit to Langmuir models to extract kinetics and thermodynamics parameters. In SPR, the adsorption onto the surface shows a biexponential behavior and this is explained as the effect of bimodal surface topology of the polycrystalline gold substrate on 3R-GBP1 binding. Depending on the concentration of the peptide, a preferential adsorption on the surface takes place with different energy levels. The kinetic parameters (e.g., K eq ∼ 107 M-1) and the binding energy (∼−8.0 kcal/mol) are comparable to synthetic-based self-assembled monolayers. The results demonstrate the potential utilization of genetically engineered inorganic surface-specific peptides as molecular substrates due to their binding specificity, stability, and functionality in an aqueous-based environment.