Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

There will be scheduled maintenance work beginning on Saturday 15th June 2019 at 8:30 am through to Sunday 16th June 2019 at 11:30 pm (BST).

During this time our website may be temporarily affected. We apologise for any inconvenience this might cause and thank you for your patience.


Issue 24, 2011
Previous Article Next Article

The role of palmitic acid in pulmonary surfactant systems by Langmuir monolayer study: Lipidpeptide interactions

Author affiliations

Abstract

Palmitic acid (PA) has been widely used as an useful and effective additive to pulmonary surfactants (PS) such as Survanta and Surfaxin. Moreover, PA has well-known biological and physicochemical properties, and its simple chemical structure allows its manufacture at low cost. However, the role and significance of PA in PS formulations are still controversial. In the present study, the PS model preparation containing PA has been investigated to clarify its additional effect (molecular recognition and interaction in particular) employing the Langmuir monolayer technique. The elucidation of the PA effect is performed by comparison with the data from its analogue (or homologue) lipids; i.e. three fatty acids and four fatty alcohols. The surface pressure (π)-molecular area (A) and surface potential (ΔV)−A isotherms for the eight DPPC/fatty lipid systems containing a PS model peptide (Hel 13-5) have been measured. In addition, the morphology and phase behavior are examined with in situ fluorescence and ex situatomic force microscopy. As a result, it is found that a balance between the hydrophilicity of the headgroup and the hydrophobicity of the tail group in the lipids is an important factor in pulmonary functions. In particular, the dissociation degree of the fatty acids, which depends on the pH or the surface pH, strongly affects their electrostatic interaction with positively charged Hel 13-5. The chain length is also significant and the carbon number 16 is found to be most appropriate. The present molecular-level information on the interaction between the lipids and Hel 13-5 in the presence of DPPC indicates that PA takes on a hydrophile–lipophile balance suitable for the PS preparation.

Graphical abstract: The role of palmitic acid in pulmonary surfactant systems by Langmuir monolayer study: Lipid–peptide interactions

Back to tab navigation

Supplementary files

Publication details

The article was received on 16 Jul 2011, accepted on 28 Aug 2011 and first published on 17 Oct 2011


Article type: Paper
DOI: 10.1039/C1SM06345F
Soft Matter, 2011,7, 11351-11359

  •   Request permissions

    The role of palmitic acid in pulmonary surfactant systems by Langmuir monolayer study: Lipidpeptide interactions

    H. Nakahara, S. Lee, Y. Shoyama and O. Shibata, Soft Matter, 2011, 7, 11351
    DOI: 10.1039/C1SM06345F

Search articles by author

Spotlight

Advertisements