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Updated: Jun 25, 2026
08:51
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
Inhomogeneity of adsorbed proteins on a solid surface
1Chemical and Biological Engineering, Missouri University of Science and Technology, Rolla, MO 65409-1230, United States. neogi@mst.edu
Colloids and Surfaces. B, Biointerfaces
|February 24, 2009
Summary
Protein adsorption on charged surfaces leads to non-uniform clustering. Electrostatic forces drive this instability, with cluster growth rate depending on protein and surface charges.
Area of Science:
- Physical Chemistry
- Surface Science
- Biophysics
Background:
- Proteins adsorb non-uniformly on solid surfaces, forming clusters.
- Previous studies ruled out bulk clustering and adsorbed phase changes in dilute, irreversible adsorption systems.
Purpose of the Study:
- To investigate the causes of protein clustering during irreversible adsorption on charged surfaces.
- To analyze the stability of protein adsorption under diffusion-limited conditions.
Main Methods:
- Developed an approximate solution for the non-equilibrium double layer in diffusion-limited adsorption.
- Performed a linear stability analysis of the adsorption process.
Main Results:
- Protein adsorption on charged surfaces is inherently unstable to small perturbations.
- Electrostatic attraction between proteins and the charged substrate overcomes small positional disturbances.
- The rate of cluster formation is directly proportional to the protein charge and substrate surface charge density.
Conclusions:
- Electrostatic interactions are the primary drivers of protein clustering during irreversible adsorption.
- The observed inhomogeneity in protein adsorption is a consequence of surface instability.
- Understanding these forces is crucial for controlling protein assembly on surfaces.
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