Fabrication, characterisation and tribological investigation of artificial skin surface lipid films

L.C. Gerhardt, A. Schiller, B. Müller, N.D. Spencer, S. Derler

Research output: Contribution to journalArticleAcademicpeer-review

36 Citations (Scopus)
2 Downloads (Pure)

Abstract

This article deals with the tribology of lipid coatings that resemble those found on human skin. In order to simulate the lipidic surface chemistry of human skin, an artificial sebum formulation that closely resembles human sebum was spray-coated onto mechanical skin models in physiologically relevant concentrations (5–100 lg/cm2). Water contact angles and surface free energies (SFEs) showed that model surfaces with B25 lg/cm2 lipids appropriately mimic the physico-chemical properties of dry, sebum-poor skin regions. In friction experiments with a steel ball, lipid-coated model surfaces demonstrated lubrication effects over a wide range of sliding velocities and normal loads. In friction measurements on model surfaces as a function of lipid-film thickness, a clear minimum in the friction coefficient (COF) was observed in the case of hydrophilic, high-SFE materials (steel, glass), with the lowest COF (&0.5) against skin model surfaces being found at 25 lg/cm2 lipids. For hydrophobic, low-SFE polymers, the COF was considerably lower (0.4 for PP, 0.16 for PTFE) and relatively independent of the lipid amount, indicating that both the mechanical and surface-chemical properties of the sliders strongly influence the friction behaviour of the skin-model surfaces. Lipid-coated skin models might be a valuable tool not only for tribologists but also for cosmetic chemists, in that they allow the objective study of friction, adhesion and wetting behaviour of liquids and emulsions on simulated skinsurface conditions.
Original languageEnglish
Pages (from-to)81-93
JournalTribology Letters
Volume34
Issue number2
DOIs
Publication statusPublished - 2009

Fingerprint

Dive into the research topics of 'Fabrication, characterisation and tribological investigation of artificial skin surface lipid films'. Together they form a unique fingerprint.

Cite this