title: A micro-fluidic study of whole blood behaviour on PMMA topographical nanostructures.
abstract: BACKGROUND
  Polymers are attractive materials for both biomedical engineering and cardiovascular applications. Although nano-topography has been found to influence cell behaviour, no established method exists to understand and evaluate the effects of nano-topography on polymer-blood interaction.
  
  
  RESULTS
  We optimized a micro-fluidic set-up to study the interaction of whole blood with nano-structured polymer surfaces under flow conditions. Micro-fluidic chips were coated with polymethylmethacrylate films and structured by polymer demixing. Surface feature size varied from 40 nm to 400 nm and feature height from 5 nm to 50 nm. Whole blood flow rate through the micro-fluidic channels, platelet adhesion and von Willebrand factor and fibrinogen adsorption onto the structured polymer films were investigated. Whole blood flow rate through the micro-fluidic channels was found to decrease with increasing average surface feature size. Adhesion and spreading of platelets from whole blood and von Willebrand factor adsorption from platelet poor plasma were enhanced on the structured surfaces with larger feature, while fibrinogen adsorption followed the opposite trend.
  
  
  CONCLUSIONS
  We investigated whole blood behaviour and plasma protein adsorption on nano-structured polymer materials under flow conditions using a micro-fluidic set-up. We speculate that surface nano-topography of polymer films influences primarily plasma protein adsorption, which results in the control of platelet adhesion and thrombus formation.
authors.affiliation: International Centre for Young Scientists, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan. c.minelli@imperial.ac.uk.
authors.forename: Caterina
authors.initials: C
authors.lastname: Minelli
authors.forename: Akemi
authors.initials: A
authors.lastname: Kikuta
authors.forename: Nataliya
authors.initials: N
authors.lastname: Tsud
authors.forename: Michael D
authors.initials: MD
authors.lastname: Ball
authors.forename: Akiko
authors.initials: A
authors.lastname: Yamamoto