Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Lubrication and Surface Properties of Adsorbed Layers of Polyelectrolytes and Proteins
KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface Chemistry.ORCID iD: 0000-0002-5444-7276
2008 (English)Doctoral thesis, comprehensive summary (Other scientific)
Abstract [en]

Friction forces between protein / polyelectrolyte layers, adsorption properties of proteins, and conformational changes due to variation in electrolyte concentration have been investigated. The aim was to obtain better understanding of adsorbed layer properties, with focus on the relation between layer structure and lubrication capabilities. The major techniques used were AFM (atomic force microscope) with colloidal probe for normal force and friction measurements together with QCM-D (quartz crystal microbalance with dissipation) for measurement of adsorption and conformational changes of adsorbed layers.

A comparison between some techniques for calibration of the AFM instrument for friction measurements was made to find the most suitably one for colloidal probe friction measurements in aqueous solutions. It is suggested that the normal and torsional Sader methods are preferred in combination with torsional detector sensitivity measurement, for which one new methodology has been proposed.

Adsorption was studied for bovine serum albumin, cytochrome c, myoglobin and mucin, whereas conformational changes of the adsorbed layer were monitored only for mucin. It was found that it was essential to take into account bulk density and viscosity changes for correct interpretations of QCM data when studying the effect of changes in electrolyte type and concentration on preadsorbed layers of mucin, and also when having different (high) concentrations of proteins in the measuring solution. The adsorbed amount of proteins appears to depend on the strength of the surface attachment, in such a manner that a too high affinity reduces the adsorbed amount.

Friction properties in aqueous solution have been studied for adsorbed layers of PEO45MEMA:METAC co-polyelectrolytes, with varying density of grafted PEO45 side chains and varying charge density, as well as for a naturally occurring polyelectrolyte (chitosan) and the glycoprotein mucin. These polymers were used to cover a wide range of different types of adsorbed layers and interactions to gain a better understanding of friction mechanisms and demands on layer properties for achieving favourable lubrication. It was found that the common features of low friction layers are that no attractive forces are present, and that excluded volume and / or electrostatic forces counteract chain interpenetration under load.

Place, publisher, year, edition, pages
Stockholm: KTH , 2008. , vii, 59 p.
Series
Trita-CHE-Report, ISSN 1654-1081 ; 2008:16
Keyword [en]
biochemistry, biomedical engineering
National Category
Physical Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-4663ISBN: 978-91-7178-891-7 (print)OAI: oai:DiVA.org:kth-4663DiVA: diva2:13308
Public defence
2008-03-27, Sal F3, KTH, Lindstedtsvägen 26, Stockholm, 10:00
Opponent
Supervisors
Note
QC 20100903Available from: 2008-03-07 Created: 2008-03-07 Last updated: 2010-09-03Bibliographically approved
List of papers
1. Comparison of different methods to calibrate torsional spring constant and photodetector for atomic force microscopy friction measurements in air and liquid
Open this publication in new window or tab >>Comparison of different methods to calibrate torsional spring constant and photodetector for atomic force microscopy friction measurements in air and liquid
2007 (English)In: Review of Scientific Instruments, ISSN 0034-6748, E-ISSN 1089-7623, Vol. 78, no 9, 093702- p.Article in journal (Refereed) Published
Abstract [en]

A number of atomic force microscopy cantilevers have been exhaustively calibrated by a number of techniques to obtain both normal and frictional force constants to evaluate the relative accuracy of the different methods. These were of either direct or indirect character-the latter relies on cantilever resonant frequencies. The so-called Sader [Rev. Sci. Instrum. 70, 3967 (1999)] and Cleveland [Rev. Sci. Instrum. 64, 403 (1993)] techniques are compared for the normal force constant calibration and while agreement was good, a systematic difference was observed. For the torsional force constants, all the techniques displayed a certain scatter but the agreement was highly encouraging. By far the simplest technique is that of Sader, and it is suggested in view of this validation that this method should be generally adopted. The issue of the photodetector calibration is also addressed since this is necessary to obtain the cantilever twist from which the torsional force is calculated. Here a technique of obtaining the torsional photodetector sensitivity by combining the direct and indirect methods is proposed. Direct calibration measurements were conducted in liquid as well as air, and a conversion factor was obtained showing that quantitative friction measurements in liquid are equally feasible provided the correct calibration is performed.

Keyword
scanning probe microscopy, lateral force, frequency-response, viscous fluids, cantilevers, surface, monolayers, tip
National Category
Chemical Engineering
Identifiers
urn:nbn:se:kth:diva-7723 (URN)10.1063/1.2779215 (DOI)000249787800011 ()2-s2.0-34848846232 (Scopus ID)
Note
QC 20100804.Available from: 2007-11-25 Created: 2007-11-25 Last updated: 2010-09-03Bibliographically approved
2. Lubrication Properties of Bottle-Brush Polyelectrolytes: An AFM Study on the Effect of Side Chain and Charge Density
Open this publication in new window or tab >>Lubrication Properties of Bottle-Brush Polyelectrolytes: An AFM Study on the Effect of Side Chain and Charge Density
2008 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 24, no 7, 3336-3347 p.Article in journal (Refereed) Published
Abstract [en]

The effect of side chain to charge ratio on the frictional properties of adsorbed layers formed by bottle-brush polyelectrolytes with poly(ethylene oxide) side chains has been investigated. The brush polyelectrolytes were preadsorbed from 0.1 mM NaNO3 solutions onto mica and silica surfaces; the interfacial friction was then measured in polyelectrolyte-free solutions via AFM (with the silica surface acting as the colloidal probe). It was concluded that the decisive factor for achieving favorable lubrication properties is the concentration of nonadsorbing poly(ethylene oxide) side chains in the interfacial region. However, contrary to what may be expected, the results showed that an ideal brush layer structure with the adsorbed polymers adopting comb-like conformation is not necessary for achieving a low coefficient of friction in the asymmetric mica-silica system. In fact, the lowest coefficient of friction (< 0.01) under applied pressures as high as 30 MPa was observed for a system with a side chain to charge ratio of 9: 1, incapable of forming brush-like layers.

Keyword
Atomic force microscopy, Charge density, Mica, Polyethylene oxides, Silica, Asymmetric mica, Bottle-brush polyelectrolytes
National Category
Physical Chemistry
Identifiers
urn:nbn:se:kth:diva-8077 (URN)10.1021/la703229n (DOI)000254480500053 ()2-s2.0-42249112292 (Scopus ID)
Note
QC 20100830. Uppdaterad från in press till published (20100830).Available from: 2008-03-07 Created: 2008-03-07 Last updated: 2010-08-30Bibliographically approved
3. Normal and Friction Forces between Mucin and Mucin-Chitosan Layers in Absence and Presence of SDS
Open this publication in new window or tab >>Normal and Friction Forces between Mucin and Mucin-Chitosan Layers in Absence and Presence of SDS
2008 (English)In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 324, no 1-2, 246-256 p.Article in journal (Refereed) Published
Abstract [en]

Employing the colloidal probe AFM technique we have investigated normal and friction forces between flat mica surfaces and silica particles coated with mucin and combined mucin-chitosan layers in presence and absence of anionic surfactant, SDS, in 30 mM NaCl solution. We have shown that the normal interactions between mucin coated mica and silica surfaces are dominated by long-range steric repulsion on both compression and decompression. Friction forces between such mucin layers are characterized by a low effective friction coefficient, mu(eff) = 0.03 +/- 0.02, which is lower than the value of 0.13 +/- 0.02 observed when chitosan layers were adsorbed. Forces between combined mucin-chitosan layers have Adsorption of chitosan on mucin results in considerable compaction of the layer, also been measured. and development of attractive forces detectable on separation. Friction between mucin-chitosan layers in 30 mM NaCl solution is high, with mu(eff) approximate to 0.4. Adsorption of additional mucin to this layer results in no improvement with respect to lubrication as compared to the mucin-chitosan layer, and mu(eff) approximate to 0.4 is We argue that the layers containing both mucin and chitosan are not strictly layered but rather observed. As a result attractive interactions between oppositely charged moieties of sialic acid strongly entangled. residues from mucin and amine groups from chitosan residing on the opposing surfaces contribute to the increased friction. The effects of SDS on normal and friction forces between combined mucin-chitosan layers were also investigated. The relation between surface interactions and friction properties is discussed.

Keyword
mucin, chitosan, SDS, friction force, AFM, lubrication, steric force, adhesion
National Category
Physical Chemistry
Identifiers
urn:nbn:se:kth:diva-8078 (URN)10.1016/j.jcis.2008.04.055 (DOI)000257232100037 ()2-s2.0-49949152619 (Scopus ID)
Note
QC 20100903. Uppdaterad från submitted till published (20100903).Available from: 2008-03-07 Created: 2008-03-07 Last updated: 2010-09-03Bibliographically approved
4. Probing Protein Adsorption onto Mercaptoundecanoic Acid Stabilized Gold Nanoparticles and Surfaces by Quartz Crystal Microbalance and ζ-Potential Measurements
Open this publication in new window or tab >>Probing Protein Adsorption onto Mercaptoundecanoic Acid Stabilized Gold Nanoparticles and Surfaces by Quartz Crystal Microbalance and ζ-Potential Measurements
Show others...
2007 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 23, no 11, 6053-6062 p.Article in journal (Refereed) Published
Abstract [en]

The adsorption characteristics of three proteins [bovine serum albumin (BSA), myoglobin (Mb), and cytochrome c (CytC)] onto self-assembled monolayers of mercaptoundecanoic acid (MUA) on both gold nanoparticles (AuNP) and gold surfaces (Au) are described. The combination of quartz crystal microbalance measurements with dissipation (QCM-D) and pH titrations of the zeta-potential provide information on layer structure, surface coverage, and potential. All three proteins formed adsorption layers consisting of an irreversibly adsorbed fraction and a reversibly adsorbed fraction. BSA showed the highest affinity for the MUA/Au, forming an irreversibly adsorbed rigid monolayer with a side-down orientation and packing close to that expected in the jamming limit. In addition, BSA showed a large change in the adsorbed mass due to reversibly bound protein. The data indicate that the irreversibly adsorbed fraction of CytC is a monolayer structure, whereas the irreversibly adsorbed Mb is present in form of a bilayer. The observation of stable BSA complexes on MUA/AuNPs at the isoelectric point by zeta-potential measurements demonstrates that BSA can sterically stabilize MUA/AuNP. On the other hand, MUA/AuNP coated with either Mb or CytC formed a reversible flocculated state at the isoelectric point. The colloidal stability differences may be correlated with weaker binding in the reversibly bound overlayer in the case of Mb and CytC as compared to BSA.

Keyword
Gold nanoparticles, Isoelectric points, PH titrations
National Category
Physical Chemistry
Identifiers
urn:nbn:se:kth:diva-8079 (URN)10.1021/la063725a (DOI)000246456700031 ()2-s2.0-34249899906 (Scopus ID)
Note

QC 20100903

Available from: 2008-03-07 Created: 2008-03-07 Last updated: 2016-05-16Bibliographically approved
5. Mucin-electrolyte interactions at the solid-liquid interface probed by QCM-D
Open this publication in new window or tab >>Mucin-electrolyte interactions at the solid-liquid interface probed by QCM-D
2008 (English)In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 24, no 7, 3348-3357 p.Article in journal (Refereed) Published
Abstract [en]

The interaction between mucin and ions has been investigated by employing the quartz crystal microbalance technique with measurement of energy dissipation. The study was partially aimed at understanding the adsorption of mucin on surfaces with different chemistry, and for this purpose, surfaces exposing COOH, OH, and CH3 groups were prepared. Mucin adsorbed to all three types of functionalized gold surfaces. Adsorption to the hydrophobic surface and to the charged hydrophilic surface (COOH) occured with high affinity despite the fact that in the latter case both mucin and the surface were negatively charged. On the uncharged hydrophilic surface exposing OH groups, the adsorption of mucin was very low. Another aim was to elucidate conformational changes induced by electrolytes on mucin layers adsorbed on hydrophobic surfaces from 30 mM NaNO3. To this end, we investigated the effect of three electrolytes with increasing cation valance: NaCl, CaCl2, and LaCl3. At low NaCl concentrations, the preadsorbed layer expands, whereas at higher concentrations of NaCl the layer becomes more compact. This swelling/compacting of the mucin layer is fully reversible for NaCl. When the mucin layer instead is exposed to CaCl2 or LaCl3, compaction is observed at I mM. For CaCl2, this process is only partially reversible, and for LaCl3, the changes are irreversible within the time frame of the experiment. Finally, mucin interaction with the DTAB cationic surfactant in an aqueous solution of different electrolytes was evaluated with turbidimetry measurements. It is concluded that the electrolytes used in this work screen the association between mucin and DTAB and that the effect increases with increasing cation valency.

Keyword
QUARTZ-CRYSTAL MICROBALANCE, BOVINE SUBMAXILLARY MUCIN, SURFACE FORCE MEASUREMENTS, CHROMIUM(III) COMPLEXES, VISCOELASTIC PROPERTIES, GOLD NANOPARTICLES, BACTERIAL ADHESION, AQUEOUS-SOLUTIONS, LIGHT-SCATTERING, ADSORPTION
National Category
Physical Chemistry
Identifiers
urn:nbn:se:kth:diva-13179 (URN)10.1021/la703366k (DOI)000254480500054 ()2-s2.0-42249102117 (Scopus ID)
Note
QC 20100705. Tidigare titel: Mucin Layer Response to Electrolytes Studied with QCM-DAvailable from: 2010-06-01 Created: 2010-06-01 Last updated: 2010-09-03Bibliographically approved
6. The Effect of Salt Concentration and Cation Valency on Interactions Between Mucin-Coated Hydrophobic Surfaces
Open this publication in new window or tab >>The Effect of Salt Concentration and Cation Valency on Interactions Between Mucin-Coated Hydrophobic Surfaces
2008 (English)In: Progress in Colloid and Polymer Science, ISSN 0340-255X, E-ISSN 1437-8027, Vol. 134, 1-10 p.Article in journal (Refereed) Published
Abstract [en]

The AFM colloidal probe technique has been utilized in order to investigate the forces acting between preadsorbed mucin layers on uncharged, hydrophobic mercaptohexadecane-coated gold surfaces. Layers with some highly extended tails are formed when the adsorption proceeds from 25 ppm mucin solution in 30 mM NaNO3. The effects of salt concentration and cation valency on the interactions have been explored using NaCl, CaCl2, and LaCl3 in the concentration range 1–100 mM. It will be shown that the results in NaCl, where the tail length decreases as the salt concentration is increased, can be rationalized by considering the polyelectrolyte nature of mucin and the screening of intralayer electrostatic interactions between charged groups, mainly anionic sialic acid. When multivalent cations are present in solution a significant compaction of the mucin layer occurs even at low concentrations (1 mM), suggesting binding of these ions to the anionic sites of mucin. The results are discussed in relation to previous data from quartz crystal microbalance measurements on the same systems.

Place, publisher, year, edition, pages
Springer, 2008
Keyword
Adsorption, Atomic force microscope, Cation binding, Mucin, Multivalent ion, Surface force, Swelling, QUARTZ-CRYSTAL MICROBALANCE, ATOMIC-FORCE MICROSCOPE, SOLID-LIQUID INTERFACE, QCM-D, CHROMIUM(III) COMPLEXES, VISCOELASTIC PROPERTIES, GLYCOPROTEINS, WATER, ELLIPSOMETRY
National Category
Physical Chemistry
Identifiers
urn:nbn:se:kth:diva-13181 (URN)10.1007/2882_2008_075 (DOI)000261378300001 ()2-s2.0-54249113712 (Scopus ID)978-3-540-68018-5 (ISBN)
Conference
43rd Biennial Meeting of the German-Colloid-Society Sch Waldthausen, Mainz, GERMANY, OCT 08-10, 2007
Note

QC 20100705

Available from: 2010-06-01 Created: 2010-06-01 Last updated: 2016-05-18Bibliographically approved

Open Access in DiVA

fulltext(1538 kB)1596 downloads
File information
File name FULLTEXT01.pdfFile size 1538 kBChecksum MD5
8c6c0b3d5672caa2995200ff16966a84f175448f1fa76b2f5002f830601cfdc7842e634b
Type fulltextMimetype application/pdf

Authority records BETA

Pettersson, Torbjörn

Search in DiVA

By author/editor
Pettersson, Torbjörn
By organisation
Surface Chemistry
Physical Chemistry

Search outside of DiVA

GoogleGoogle Scholar
Total: 1596 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 771 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf