Adhesive and conformational behaviour of mycolic acid monolayers

Zhenyu Zhang, Yu Pen, Robert G. J. Edyvean, Steven A. Banwart, Robert M. Dalgliesh, Mark Geoghegan

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

We have studied the pH-dependent interaction between mycolic acid (MA) monolayers and hydrophobic and hydrophilic surfaces using molecular (colloidal probe) force spectroscopy. In both cases, hydrophobic and hydrophilic monolayers (prepared by Langmuir–Blodgett and Langmuir–Schaefer deposition on silicon or hydrophobized silicon substrates, respectively) were studied. The force spectroscopy data, fitted with classical DLVO (Derjaguin, Landau, Verwey, and Overbeek) theory to examine the contribution of electrostatic and van der Waals forces, revealed that electrostatic forces are the dominant contribution to the repulsive force between the approaching colloidal probe and MA monolayers. The good agreement between data and the DLVO model suggest that beyond a few nm away from the surface, hydrophobic, hydration, and specific chemical bonding are unlikely to contribute to any significant extent to the interaction energy between the probe and the surface. The pH-dependent conformation of MA molecules in the monolayer at the solid-liquid interface was studied by ellipsometry, neutron reflectometry, and with a quartz crystal microbalance. Monolayers prepared by the Langmuir–Blodgett method demonstrated a distinct pH-responsive behaviour, while monolayers prepared by the Langmuir–Schaefer method were less sensitive to pH variation. It was found that the attachment of water molecules plays a vital role in determining the conformation of the MA monolayers.
LanguageEnglish
Pages1829-1839
Number of pages11
JournalBBA - Biomembranes
Volume1798
Issue number9
Early online date4 Jun 2010
DOIs
Publication statusPublished - Sep 2010

Fingerprint

Mycolic Acids
Adhesives
Monolayers
Acids
Silicon
Static Electricity
Spectrum Analysis
Quartz Crystal Microbalance Techniques
Molecular Probes
Neutrons
Conformations
Spectroscopy
Van der Waals forces
Molecules
Electrostatic force
Quartz crystal microbalances
Ellipsometry
Water
Hydration
Electrostatics

Keywords

  • mycolic acid
  • neutron reflectometry
  • colloidal force spectroscopy
  • DLVO

Cite this

Zhang, Z., Pen, Y., Edyvean, R. G. J., Banwart, S. A., Dalgliesh, R. M., & Geoghegan, M. (2010). Adhesive and conformational behaviour of mycolic acid monolayers. BBA - Biomembranes, 1798(9), 1829-1839. https://doi.org/10.1016/j.bbamem.2010.05.024
Zhang, Zhenyu ; Pen, Yu ; Edyvean, Robert G. J. ; Banwart, Steven A. ; Dalgliesh, Robert M. ; Geoghegan, Mark. / Adhesive and conformational behaviour of mycolic acid monolayers. In: BBA - Biomembranes. 2010 ; Vol. 1798, No. 9. pp. 1829-1839.
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Zhang, Z, Pen, Y, Edyvean, RGJ, Banwart, SA, Dalgliesh, RM & Geoghegan, M 2010, 'Adhesive and conformational behaviour of mycolic acid monolayers' BBA - Biomembranes, vol. 1798, no. 9, pp. 1829-1839. https://doi.org/10.1016/j.bbamem.2010.05.024

Adhesive and conformational behaviour of mycolic acid monolayers. / Zhang, Zhenyu; Pen, Yu; Edyvean, Robert G. J.; Banwart, Steven A. ; Dalgliesh, Robert M.; Geoghegan, Mark.

In: BBA - Biomembranes, Vol. 1798, No. 9, 09.2010, p. 1829-1839.

Research output: Contribution to journalArticle

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T1 - Adhesive and conformational behaviour of mycolic acid monolayers

AU - Zhang, Zhenyu

AU - Pen, Yu

AU - Edyvean, Robert G. J.

AU - Banwart, Steven A.

AU - Dalgliesh, Robert M.

AU - Geoghegan, Mark

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M3 - Article

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JF - BBA - Biomembranes

SN - 0005-2736

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Zhang Z, Pen Y, Edyvean RGJ, Banwart SA, Dalgliesh RM, Geoghegan M. Adhesive and conformational behaviour of mycolic acid monolayers. BBA - Biomembranes. 2010 Sep;1798(9):1829-1839. https://doi.org/10.1016/j.bbamem.2010.05.024