Hemocompatibility of Titanium Nitride

Abstract

The left ventricular assist device is based on the principle of the Maillard-Wenkel rotative pump. The materials which make up the pump must present particular mechanical, tribological, thermal and chemical properties. Titanium nitride (TiN) because of its surface properties and graphite because of its bulk characteristics have been chosen. The present study evaluated the in vitro hemocompatibility of TiN coating deposited by the chemical vapor deposition process. Protein adsorption, platelet retention and hemolysis tests have been carried out. In spite of some disparities, the TiN behavior towards albumin and fibrinogen is interesting, compared with the one of a reference medical grade elastomer. The platelet retention test gives similar results as those achieved with the same elastomer. The hemolysis percentage is near to zero. TiN shows interesting characteristics, as far as mechanical and tribological problems are concerned, and presents very encouraging blood tolerability properties.

Protein adsorption and platelet attachment and activation, on TiN, TiC, and DLC coatings on titanium for cardiovascular applications

“…The analysis of protein adsorption was performed in plasma free solution to establish baseline interactions between the surfaces and pure plasma proteins. Although it is possible that the absence of plasma in the assay could alter the kinetics of surface protein adsorption and consequently affect platelet substrate interactions, Dion et al 29,30 performed similar studies in plasma and produced comparable adsorption data to our own. Protein adsorption on the surfaces was studied at an incubation time of 60 min, as this was the longest incubation period used for the platelet rich plasma, and the only time period at which significant variations in platelet behavior were observed.…”

“…It would be of interest to study their adsorption behavior under conditions of competitive adsorption, as is more likely to occur in practice. 40 Dion et al 29,30 proposed that it is the ratio of albumin to fibrinogen that is important when assessing the adhesion of blood platelets to artificial surfaces, and that the higher the ratio, the lower the number of adhering platelets. The ratio of albumin-to-fibrinogen adsorption obtained in this work, as determined by mean absorbance values, is shown in Figure 9.…”

“…Although these interactions give an indication as to the compatibility of the coatings with surrounding connective tissue, they do not adequately address the acceptability of these materials in blood interfacing applications, such as heart valve prostheses. Reports regarding the hemocompatibility of DLC/TiN are very limited, 13,[29][30][31] and are generally based on counting the number of radioactively labeled platelets and plasma proteins following contact with the material, without any direct observation as to the activated state of the platelets.…”

Application of Dental Implants Coated with Titanium Nitride: The Experimental Study with Porphyromonas gingivalis Infection

“…TiN is mainly used as a coating to enhance other materials. TiN shows encouraging blood tolerability properties with hemolysis percentage near zero (Dion et al, 1992). Therefore, TiN-coatings are used in cardiology for ventricular assist devices in patients with heart failure (Sin et al, 2009) and for pacemaker leads (Schaldach et al, 1989).…”

Relative Contributions of Surface Roughness and Crystalline Structure to the Biocompatibility of Titanium Nitride and Titanium Oxide Coatings Deposited by PVD and TPS Coatings

“…With the development of the thin coating technology, recent studies have started to focus on creating unique thin coatings of TiN and TiO 2 to control cellular functions [10][11][12]. TiN has drawn attention due to its mechanical properties, such as hardness, corrosion resistance, shear strength [8,13,14], and biological properties such as biocompatibility [15] and haemocompatibility [16][17][18]. The high hardness and low coefficient of friction of these coatings have been exploited for applications such as drills or cutting tools leading to increases in lifetime as excellent tribological coatings [18,19].…”