title: Real-time monitoring of surface-confined platelet activation on TiO₂.
abstract: For the development of advanced hemocompatible biomaterial functions, there is an unmet demand for in vitro evaluation techniques addressing platelet-surface interactions. We show that the quartz crystal microbalance with dissipation (QCM-D) monitoring technique, here combined with light microscopy, provides a surface sensitive technique that allows for real-time monitoring of the activation and aggregation of the surface-confined platelets on TiO2. The QCM-D signal monitored during adhesion and activation of platelets on TiO2 coated surfaces was found to be different in platelet-poor and platelet-rich environment although light microscopy images taken for each of the two cases looked essentially the same. Interestingly, aggregation of activated platelets was only observed in a protein-rich environment. Our results show that a layer of plasma proteins between the TiO2 surface and the platelets strongly influences the coupling between the platelets and the underlying substrate, explaining both the observed QCM-D signals and the ability of the platelets to aggregate.
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden. Electronic address: angelika.kunze@chalmers.se.
authors.forename: Angelika
authors.initials: A
authors.lastname: Kunze
authors.affiliation: Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy at the University of Gothenburg, 413 45 Göteborg, Sweden.
authors.forename: Camilla
authors.initials: C
authors.lastname: Hesse
authors.affiliation: Department of Applied Physics, Chalmers University of Technology, 412 96 Göteborg, Sweden.
authors.forename: Sofia
authors.initials: S
authors.lastname: Svedhem
mesh_terms: D001792:Blood Platelets / Q000737:chemistry*; D006801:Humans; D010316:Particle Size; D058525:Quartz Crystal Microbalance Techniques; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry*
chemical_list: C009495:titanium dioxide; D014025:Titanium
keywords: Aggregation; Platelet activation; QCM-D; TiO(2)