How surface wettability affects the binding, folding, and dynamics of hydrophobic polymers at interfaces

We present an extensive molecular simulation study of the behavior of a flexible hydrophobic 25-mer polymer at interfaces presenting a range of chemistries from hydrophobic (-CH(3)) to hydrophilic (-CONH(2)). We quantify the free energy of adsorption, conformational equilibria, and translational and...

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Bibliographische Detailangaben
Veröffentlicht in:Langmuir : the ACS journal of surfaces and colloids. - 1999. - 25(2009), 22 vom: 17. Nov., Seite 13092-9
1. Verfasser: Jamadagni, Sumanth N (VerfasserIn)
Weitere Verfasser: Godawat, Rahul, Garde, Shekhar
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2009
Zugriff auf das übergeordnete Werk:Langmuir : the ACS journal of surfaces and colloids
Schlagworte:Journal Article Research Support, N.I.H., Extramural Research Support, U.S. Gov't, Non-P.H.S. Polymers
Beschreibung
Zusammenfassung:We present an extensive molecular simulation study of the behavior of a flexible hydrophobic 25-mer polymer at interfaces presenting a range of chemistries from hydrophobic (-CH(3)) to hydrophilic (-CONH(2)). We quantify the free energy of adsorption, conformational equilibria, and translational and conformational dynamics of the polymer at these diverse interfaces. Water-mediated interactions drive the polymer to adsorb strongly at a hydrophobic interface and repel it from hydrophilic ones. At hydrophilic surfaces, van der Waals interactions between the polymer and the surface mitigate this water-mediated repulsion, leading to weak adsorption of the polymer. Although the polymer is strongly adsorbed to hydrophobic surfaces, it is also most dynamic there. Translational diffusion and conformational dynamics are faster at hydrophobic surfaces compared to those at hydrophilic ones. In bulk water, the polymer collapses into compact globular shapes, whereas the thermodynamic stability of folded polymers is significantly lowered at hydrophobic surfaces. The polymer spreads into pancake-like 2D conformations at hydrophobic surfaces and gradually beads up into globular shapes as the surface is made more hydrophilic. Interestingly, the binding thermodynamics and dynamics correlate with macroscopic droplet contact angles that characterize the wetting properties of the different interfaces
Beschreibung:Date Completed 21.01.2010
Date Revised 18.11.2010
published: Print
Citation Status MEDLINE
ISSN:1520-5827
DOI:10.1021/la9011839