In-vitro blood compatibility of a-C : H : Si and a-C : H thin films

TIT Okpalugo, AA Ogwu, PD Maguire, JAD McLaughlin, DG Hirst

Research output: Contribution to journalArticle

49 Citations (Scopus)

Abstract

Carbon-based materials, for example pyrolytic carbon, have been successfully applied as artificial clinical heart valve coatings but due to ease of availability, processing, increased hardness, corrosion and scratch resistance, DLC has recently attracted attention for biomedical applications. Although often cited as having bio-compatible properties there has been little systematic study of DLC and how film structure may affect such properties. RF PECVD a-C:H and Si-doped a-C:H:Si films were deposited and in-vitro blood compatibility (haemocompatibility) investigated by the use of human microvascularendothelial cells (HMEC) on one end of the scale and platelets on the other, in order to assess the potential of DLC in biomedicine and surgical applications. Increased electronic conduction, decreased work function and decreased surface bond energy (with a high dispersive component) in the absence of graphitisation improved the blood compatibility of a-C:H and a-C:H:Si thin films. Changes in the nanostructure, surface energy and electrical properties was observed with silicon doping while thermal annealing also altered the electrical properties, reduced intrinsic compressive stress and at higher temperatures (> 400 degreesC) induced graphitisation. Increased HMEC adhesion (approx. 6x) and/or decreased platelets aggregation (approx. 6x) is associated with lower resistivity, work function and surface energy in the thin films where there is no graphitisation. Graphitisation, however, despite the lower resistivity and work function, leads to lower HMEC adhesion and increased platelets aggregation. Si-doped a-C:H coatings deposited under optimal conditions are a significant factor in developing haemocompatible medical implants and devices. (C) 2003 Elsevier B.V. All rights reserved.
LanguageEnglish
Pages1088-1092
JournalDiamond and Related Materials
Volume13
Issue number4-8
DOIs
Publication statusPublished - Apr 2004

Fingerprint

Graphitization
Blood
Platelets
Thin films
Cell adhesion
Interfacial energy
Electric properties
Agglomeration
Coatings
Carbon
Silicon
Plasma enhanced chemical vapor deposition
Compressive stress
Nanostructures
Hardness
Doping (additives)
Availability
Annealing
Corrosion
Processing

Keywords

  • blood compatibility
  • cell adhesion
  • silicon doping
  • surface bond energy

Cite this

Okpalugo, TIT ; Ogwu, AA ; Maguire, PD ; McLaughlin, JAD ; Hirst, DG. / In-vitro blood compatibility of a-C : H : Si and a-C : H thin films. In: Diamond and Related Materials. 2004 ; Vol. 13, No. 4-8. pp. 1088-1092.
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In-vitro blood compatibility of a-C : H : Si and a-C : H thin films. / Okpalugo, TIT; Ogwu, AA; Maguire, PD; McLaughlin, JAD; Hirst, DG.

In: Diamond and Related Materials, Vol. 13, No. 4-8, 04.2004, p. 1088-1092.

Research output: Contribution to journalArticle

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T1 - In-vitro blood compatibility of a-C : H : Si and a-C : H thin films

AU - Okpalugo, TIT

AU - Ogwu, AA

AU - Maguire, PD

AU - McLaughlin, JAD

AU - Hirst, DG

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