Periodic protein adsorption at the gold/biotin aqueous solution interface: evidence of kinetics with time delay

• Published in: Scientific reports Vol. 6; no. 1; p. 36232
• Main Authors: Neff, H., Laborde, H. M., Lima, A. M. N.
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 03.11.2016; Nature Publishing Group
• Subjects: 631/57/2272/1590; 639/638/542/970; 82/103; 9/10; Adsorption; Aqueous solutions; Biotin; Carbon monoxide; Gold; Growth rate; Humanities and Social Sciences; Kinetics; multidisciplinary; Oscillations; Oxidation; Platinum; Proteins; Science; Surface plasmon resonance
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/srep36232

An oscillatory molecular adsorption pattern of the protein neutravidin from aqueous solution onto gold, in presence of a pre-deposited self assembled mono-molecular biotin film, is reported. Real time surface Plasmon resonance sensing was utilized for evaluation of the adsorption kinetics. Two different fractions were identified: in the initial phase, protein molecules attach irreversibly onto the Biotin ligands beneath towards the jamming limit, forming a neutravidin-biotin fraction. Afterwards, the growth rate exhibits distinct, albeit damped adsorption-desorption oscillations over an extended time span, assigned to a quasi reversibly bound fraction. These findings agree with, and firstly confirm a previously published model, proposing macro-molecular adsorption with time delay. The non-linear dynamic model is applicable to and also resembles non-damped oscillatory binding features of the hetero-catalytic oxidation of carbon monoxide molecules on platinum in the gas phase. An associated surface residence time can be linked to the dynamics and time scale required for self-organization.