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Updated: May 18, 2026
08:51
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
Effect of surface wettability on ion-specific protein adsorption
Xiaowen Wang1, Guangming Liu, Guangzhao Zhang
1Department of Chemical Physics, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, PR China 230026.
Langmuir : the ACS Journal of Surfaces and Colloids
|September 21, 2012
Summary
Surface wettability influences bovine serum albumin (BSA) adsorption, revealing ion-specific effects at pH 3.8 and pH 7.4. Protein structural rearrangements are key in anion-specific adsorption processes.
Area of Science:
- Biomaterials Science
- Surface Chemistry
- Protein Adsorption
Background:
- Understanding protein adsorption is crucial for biomaterial development and biosensor design.
- Surface properties significantly influence protein-surface interactions.
- Bovine serum albumin (BSA) is a model protein for studying adsorption phenomena.
Purpose of the Study:
- To investigate the impact of surface wettability on BSA adsorption.
- To explore ion-specific adsorption mechanisms of BSA.
- To elucidate the role of surface chemistry in protein-surface interactions.
Main Methods:
- Quartz crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR) were employed.
- Self-assembled monolayers with varying wettability (molar fraction of 1-dodecanethiol) were used.
- Adsorption kinetics and layer properties were analyzed at different pH values.
Main Results:
- BSA adsorption showed non-monotonous and gradual changes with surface wettability at pH 3.8 and pH 7.4, respectively.
- A rigid BSA layer was formed, with minor differences between QCM-D and SPR measurements attributed to coupled water.
- Specific anion effects were observed at pH 3.8, while cation specificity was absent at pH 7.4.
Conclusions:
- Surface wettability is a critical factor governing BSA adsorption behavior.
- Distinct kinetic processes, including anion-specific interactions and protein structural rearrangements, were identified.
- The findings provide insights into designing surfaces for controlled protein adsorption in various applications.
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