Interfacial energetics of globular–blood protein adsorption to a hydrophobic interface from aqueous-buffer solution
Open Access
- 17 October 2005
- journal article
- Published by The Royal Society in Journal of The Royal Society Interface
- Vol. 3 (7), 283-301
- https://doi.org/10.1098/rsif.2005.0087
Abstract
Adsorption isotherms of nine globular proteins with molecular weight (MW) spanning 10–1000 kDa confirm that interfacial energetics of protein adsorption to a hydrophobic solid/aqueous-buffer (solid–liquid, SL) interface are not fundamentally different than adsorption to the water–air (liquid–vapour, LV) interface. Adsorption dynamics dampen to a steady-state (equilibrium) within a 1 h observation time and protein adsorption appears to be reversible, following expectations of Gibbs' adsorption isotherm. Adsorption isotherms constructed from concentration-dependent advancing contact angles θ a of buffered-protein solutions on methyl-terminated, self-assembled monolayer surfaces show that maximum advancing spreading pressure, , falls within a relatively narrow band characteristic of all proteins studied, mirroring results obtained at the LV surface. Furthermore, Π a isotherms exhibited a ‘Traube-rule-like’ progression in MW similar to the ordering observed at the LV surface wherein molar concentrations required to reach a specified spreading pressure Π a decreased with increasing MW. Finally, neither Gibbs' surface excess quantities [ Γ sl − Γ sv ] nor Γ lv varied significantly with protein MW. The ratio {[ Γ sl − Γ sv ]/ Γ lv }∼1, implying both that Γ sv ∼0 and chemical activity of protein at SL and LV surfaces was identical. These results are collectively interpreted to mean that water controls protein adsorption to hydrophobic surfaces and that the mechanism of protein adsorption can be understood from this perspective for a diverse set of proteins with very different composition.Keywords
This publication has 44 references indexed in Scilit:
- Scaled interfacial activity of proteins at a hydrophobic solid/aqueous‐buffer interfaceJournal of Biomedical Materials Research Part A, 2005
- Liquid–vapor interfacial tension of blood plasma, serum and purified protein constituents thereofBiomaterials, 2005
- Scaled interfacial activity of proteins at the liquid–vapor interfaceJournal of Biomedical Materials Research Part A, 2003
- On the Necessity of Using Activities in the Gibbs EquationThe Journal of Physical Chemistry B, 1999
- Energy Dissipation Kinetics for Protein and Antibody−Antigen Adsorption under Shear Oscillation on a Quartz Crystal MicrobalanceLangmuir, 1998
- Conformational Energy Calculations on Polypeptides and ProteinsChemical Reviews, 1994
- A graphical method for predicting surfactant and protein adsorption propertiesLangmuir, 1993
- Practical use of concentration-dependent contact angles as a measure of solid-liquid adsorption. 2. Experimental aspectsLangmuir, 1992
- Practical use of concentration-dependent contact angles as a measure of solid-liquid adsorption. 1. Theoretical aspectsLangmuir, 1992
- Adsorption of DNA at the air-water interfaceThe Journal of Physical Chemistry, 1968