title: Blood compatibility of magnesium and its alloys.
abstract: BACKGROUND
  Blood compatibility analysis in the field of biomaterials is a highly controversial topic. Especially for degradable materials like magnesium and its alloys no established test methods are available.
  
  
  OBJECTIVE
  The purpose of this study was to apply advanced test methodology for the analysis of degrading materials to get a mechanistic insight into the corrosion process in contact with human blood and plasma.
  
  
  RESULTS
  Pure magnesium and two magnesium alloys were analysed in a modified Chandler-Loop setup. Standard clinical parameters were determined, and a thorough analysis of the resulting implant surface chemistry was performed. The contact of the materials to blood evoked an accelerated inflammatory and cell-induced osteoconductive reaction. Corrosion products formed indicate a more realistic, in vivo like situation.
  
  
  CONCLUSIONS
  The active regulation of corrosion mechanisms of magnesium alloys by different cell types should be more in the focus of research to bridge the gap between in vitro and in vivo observations and to understand the mechanism of action. This in turn could lead to a better acceptance of these materials for implant applications.
  
  
  CONCLUSIONS
  The presented study deals with the first mechanistic insights during whole human blood contact and its influence on a degrading magnesium-based biomaterial. The combination of clinical parameters and corrosion layer analysis has been performed for the first time. It could be of interest due to the intended use of magnesium-based stents and for orthopaedic applications for clinical applications. An interest for the readers of Acta Biomaterialia may be given, as one of the first clinically approved magnesium-based devices is a wound-closure device, which is in direct contact with blood. Moreover, for orthopaedic applications also blood contact is of high interest. Although this is not the focus of the manuscript, it could help to rise awareness for potential future applications.
authors.affiliation: Helmholtz-Zentrum Geesthacht, Institute of Material Research, Department for Material Design and Characterisation, Max-Planck-Str. 1, 21502 Geesthacht, Germany. Electronic address: frank.feyerabend@hzg.de.
authors.forename: Frank
authors.initials: F
authors.lastname: Feyerabend
authors.affiliation: Department of Cardiovascular Surgery, Clinical Research Laboratory, University Hospital Tuebingen, Calwerstr. 7/1, 72076 Tuebingen, Germany.
authors.forename: Hans-Peter
authors.initials: HP
authors.lastname: Wendel
authors.affiliation: University of Hamburg, Department of Earth Sciences, Grindelallee 48, 20146 Hamburg, Germany.
authors.forename: Boriana
authors.initials: B
authors.lastname: Mihailova
authors.affiliation: University of Hamburg, Department of Earth Sciences, Grindelallee 48, 20146 Hamburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Heidrich
authors.affiliation: Helmholtz-Zentrum Geesthacht, Institute of Material Research, Department for Material Design and Characterisation, Max-Planck-Str. 1, 21502 Geesthacht, Germany.
authors.forename: Nezha Ahmad
authors.initials: NA
authors.lastname: Agha
authors.affiliation: University of Hamburg, Department of Earth Sciences, Grindelallee 48, 20146 Hamburg, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Bismayer
authors.affiliation: Helmholtz-Zentrum Geesthacht, Institute of Material Research, Department for Material Design and Characterisation, Max-Planck-Str. 1, 21502 Geesthacht, Germany.
authors.forename: Regine
authors.initials: R
authors.lastname: Willumeit-Römer
mesh_terms: D000328:Adult; D000497:Alloys / Q000494:pharmacology*; D000990:Antithrombin III / Q000378:metabolism; D001792:Blood Platelets / Q000187:drug effects / Q000378:metabolism; D002118:Calcium / Q000032:analysis; D003343:Corrosion; D006801:Humans; D007477:Ions; D008274:Magnesium / Q000032:analysis / Q000494:pharmacology*; D008422:Materials Testing; D010087:Oxides / Q000032:analysis; D010447:Peptide Hydrolases / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D055815:Young Adult
chemical_list: D000497:Alloys; D007477:Ions; D010087:Oxides; C046193:antithrombin III-protease complex; D000990:Antithrombin III; D010447:Peptide Hydrolases; D008274:Magnesium; D002118:Calcium
keywords: Carbonic anhydrase; Cell–material interactions; Chandler-Loop system; Inflammation; Magnesium alloys