Existence of hydration forces in the interaction between apoferritin molecules adsorbed on silica surfaces
The atomic force microscope, together with the colloid probe technique, has become a very useful instrument to measure interaction forces between two surfaces. Its potential has been exploited in this work to study the interaction between protein (apoferritin) layers adsorbed on silica surfaces and...
Veröffentlicht in: | Langmuir : the ACS journal of surfaces and colloids. - 1999. - 21(2005), 21 vom: 11. Okt., Seite 9544-54 |
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1. Verfasser: | |
Weitere Verfasser: | , , , , |
Format: | Aufsatz |
Sprache: | English |
Veröffentlicht: |
2005
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Zugriff auf das übergeordnete Werk: | Langmuir : the ACS journal of surfaces and colloids |
Schlagworte: | Journal Article Research Support, Non-U.S. Gov't Silicon Dioxide 7631-86-9 Apoferritins 9013-31-4 |
Zusammenfassung: | The atomic force microscope, together with the colloid probe technique, has become a very useful instrument to measure interaction forces between two surfaces. Its potential has been exploited in this work to study the interaction between protein (apoferritin) layers adsorbed on silica surfaces and to analyze the effect of the medium conditions (pH, salt concentration, salt type) on such interactions. It has been observed that the interaction at low salt concentrations is dominated by electrical double layer (at large distances) and steric forces (at short distances), the latter being due to compression of the protein layers. The DLVO theory fits these experimental data quite well. However, a non-DLVO repulsive interaction, prior to contact of the protein layers, is observed at high salt concentration above the isoelectric point of the protein. This behavior could be explained if the presence of hydration forces in the system is assumed. The inclusion of a hydration term in the DLVO theory (extended DLVO theory) gives rise to a better agreement between the theoretical fits and the experimental results. These results seem to suggest that the hydration forces play a very important role in the stability of the proteins in the physiological media |
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Beschreibung: | Date Completed 10.04.2007 Date Revised 06.10.2005 published: Print Citation Status MEDLINE |
ISSN: | 1520-5827 |