Publication detail

In situ measurements of thin films in bovine serum lubricated contacts using optical interferometry

VRBKA, M. KŘUPKA, I. HARTL, M. NÁVRAT, T. GALLO, J. GALANDÁKOVÁ, A.

Original Title

In situ measurements of thin films in bovine serum lubricated contacts using optical interferometry

Type

journal article in Web of Science

Language

English

Original Abstract

The aim of this study is to consider the relevance of in situ measurements of bovine serum film thickness in the optical test device that could be related to the function of the artificial hip joint. It is mainly focussed on the effect of the hydrophobicity or hydrophilicity of the transparent surface and the effect of its geometry. Film thickness measurements were performed using ball-on-disc and lens-on-disc configurations of optical test device as a function of time. Chromatic interferograms were recorded with a high-speed complementary metal-oxide semiconductor digital camera and evaluated with thin film colorimetric interferometry. It was clarified that a chromium layer covering the glass disc has a hydrophobic behaviour which supports the adsorption of proteins contained in the bovine serum solution, thereby a thicker lubricating film is formed. On the contrary, the protein film formation was not observed when the disc was covered with a silica layer having a hydrophilic behaviour. In this case, a very thin lubricating film was formed only due to the hydrodynamic effect. Metal and ceramic balls have no substantial effect on lubricant film formation although their contact surfaces have relatively different wettability. It was confirmed that conformity of contacting surfaces and kinematic conditions has fundamental effect on bovine serum film formation. In the ball-on-disc configuration, the lubricant film is formed predominantly due to protein aggregations, which pass through the contact zone and increase the film thickness. In the more conformal ball-on-lens configuration, the lubricant film is formed predominantly due to hydrodynamic effect, thereby the film thickness is kept constant during measurement.

Keywords

Total hip replacement, conformity of surfaces, hydrophobicity, hydrophilicity, bovine serum, protein formation, lubrication, film thickness, colorimetric interferometry

Authors

VRBKA, M.; KŘUPKA, I.; HARTL, M.; NÁVRAT, T.; GALLO, J.; GALANDÁKOVÁ, A.

RIV year

2014

Released

7. 1. 2014

Publisher

SAGE Publications Ltd

Location

Velká Británie

ISBN

0954-4119

Periodical

PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE

Year of study

228

Number

2

State

United Kingdom of Great Britain and Northern Ireland

Pages from

149

Pages to

158

Pages count

10

BibTex

@article{BUT104824,
  author="VRBKA, M. and KŘUPKA, I. and HARTL, M. and NÁVRAT, T. and GALLO, J. and GALANDÁKOVÁ, A.",
  title="In situ measurements of thin films in bovine serum lubricated contacts using optical interferometry",
  journal="PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART H-JOURNAL OF ENGINEERING IN MEDICINE",
  year="2014",
  volume="228",
  number="2",
  pages="149--158",
  doi="10.1177/0954411913517498",
  issn="0954-4119"
}