title: Evaluation of wettability and surface energy of native Nitinol surfaces in relation to hemocompatibility.
abstract: In the present study the dependence of Nitinol contact angles and surface energy on surface treatment is explored in order to better understand the material hemocompatibility that was evaluated in our previous studies. It is found that in the group of surfaces: (1) mechanically polished, (2) additionally heat treated, (3) chemically etched, and (4) additionally boiled in water, and (5) further heat treated, the contact angle could vary in the 50°-80° hydrophobic range and the total surface free energy in the 34-53 mN/m range. The polar surface energy, varying from 5 to 29 mN/m, constitutes a decisive contribution to the total energy change, and it seems to be a direct function of the Nitinol surface chemistry. Based on the complex analysis of surface energy together with the earlier results on electrochemistry and hemocompatibility it is concluded that the alteration of the polar component of surface energy and thrombogenicity is due to changes of the electron-acceptor/electron-donor character of native Nitinol surfaces during surface treatments.
authors.affiliation: Ames Laboratory-DOE, Iowa State University, Ames, IA 50011, USA.
authors.forename: Svetlana A
authors.initials: SA
authors.lastname: Shabalovskaya
authors.affiliation: Institute of Materials Science and Technology, Friedrich-Schiller University, Löbdergraben 32, 07743 Jena, Germany; Department of Bioinformatics, Friedrich-Schiller University, Ernst-Abbe-Platz 2, 07743 Jena, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Siegismund
authors.affiliation: Institute of Materials Science and Technology, Friedrich-Schiller University, Löbdergraben 32, 07743 Jena, Germany.
authors.forename: Erik
authors.initials: E
authors.lastname: Heurich
authors.affiliation: Institute of Materials Science and Technology, Friedrich-Schiller University, Löbdergraben 32, 07743 Jena, Germany. Electronic address: M.Rettenmayr@uni-jena.de.
authors.forename: Markus
authors.initials: M
authors.lastname: Rettenmayr
mesh_terms: D000327:Adsorption; D000418:Albumins; D000497:Alloys / Q000737:chemistry*; D001672:Biocompatible Materials / Q000737:chemistry*; D005340:Fibrinogen; D005559:Formamides / Q000737:chemistry; D008422:Materials Testing; D013816:Thermodynamics; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: D000418:Albumins; D000497:Alloys; D001672:Biocompatible Materials; D005559:Formamides; D014867:Water; C013616:nitinol; C031066:formamide; D005340:Fibrinogen