Apparent Activation Energies Associated with Protein Dynamics on Hydrophobic and Hydrophilic Surfaces
| Autor: | Mark Kastantin, Blake B. Langdon, Daniel K. Schwartz |
|---|---|
| Jazyk: | angličtina |
| Předmět: |
Surface Properties
Diffusion Population Analytical chemistry Biophysics 02 engineering and technology Activation energy 010402 general chemistry 01 natural sciences symbols.namesake chemistry.chemical_compound Desorption Organic chemistry Animals Humans education Surface diffusion Arrhenius equation education.field_of_study Total internal reflection fluorescence microscope Proteins Fibrinogen Trimethylsilane Serum Albumin Bovine Silanes 021001 nanoscience & nanotechnology Silicon Dioxide 0104 chemical sciences Kinetics chemistry symbols Thermodynamics Cattle Adsorption 0210 nano-technology Hydrophobic and Hydrophilic Interactions |
| Zdroj: | Biophysical Journal. (11):2625-2633 |
| ISSN: | 0006-3495 |
| DOI: | 10.1016/j.bpj.2012.04.027 |
| Popis: | With the use of single-molecule total internal reflection fluorescence microscopy (TIRFM), the dynamics of bovine serum albumin (BSA) and human fibrinogen (Fg) at low concentrations were observed at the solid-aqueous interface as a function of temperature on hydrophobic trimethylsilane (TMS) and hydrophilic fused silica (FS) surfaces. Multiple dynamic modes and populations were observed and characterized by their surface residence times and squared-displacement distributions (surface diffusion). Characteristic desorption and diffusion rates for each population/mode were generally found to increase with temperature, and apparent activation energies were determined from Arrhenius analyses. The apparent activation energies of desorption and diffusion were typically higher on FS than on TMS surfaces, suggesting that protein desorption and mobility were hindered on hydrophilic surfaces due to favorable protein-surface and solvent-surface interactions. The diffusion of BSA on TMS appeared to be activationless for several populations, whereas diffusion on FS always exhibited an apparent activation energy. All activation energies were small in absolute terms (generally only a few kBT), suggesting that most adsorbed protein molecules are weakly bound and move and desorb readily under ambient conditions. |
| Databáze: | OpenAIRE |
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