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Updated: May 11, 2026
09:48
In Situ Characterization of Hydrated Proteins in Water by SALVI and ToF-SIMS
Published on: February 15, 2016
Elucidating changes in interfacial water structure upon protein adsorption.
1Department of Chemistry, Texas A&M University, College Station, TX 77842-3012, USA.
Summary
Sum-frequency generation (SFG) spectroscopy revealed that bovine serum albumin (BSA) adsorption onto silica surfaces disorders interfacial water. This occurs due to a reduced surface charge, affecting hydrogen bonding in the water molecules.
Area of Science:
- Surface Chemistry
- Spectroscopy
- Biophysics
Background:
- Protein adsorption is crucial in biological and industrial applications.
- Understanding interfacial water structure during adsorption is key.
- Silica surfaces and bovine serum albumin (BSA) are common models.
Purpose of the Study:
- To investigate the effect of bovine serum albumin (BSA) adsorption on interfacial water structure at a silica surface.
- To utilize sum-frequency generation (SFG) spectroscopy to probe these changes.
- To correlate changes in water structure with surface properties like ξ-potential.
Main Methods:
- Sum-frequency generation (SFG) spectroscopy was employed.
- Bovine serum albumin (BSA) was adsorbed onto a silica surface from solution at pH 8.0.
- Interfacial water structure and surface ξ-potential were analyzed.
Main Results:
- BSA adsorption led to attenuated SFG intensity, indicating less ordered interfacial water.
- A reduction in surface ξ-potential was observed.
- The SFG spectrum revealed changes in hydrogen bonding of water molecules, with both stronger (≈3200 cm(-1)) and weaker (3200 cm(-1)) bonds.
Conclusions:
- Protein adsorption significantly alters interfacial water ordering.
- The observed changes in water structure are linked to modifications in surface charge (ξ-potential).
- SFG spectroscopy is a powerful tool for studying complex surface phenomena like protein adsorption.
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