The measurement of the strength of bonds between biomaterials and cells is a major challenge in biotribology since it allows for the identification of different species in adhesion phenomena. Biomaterials, such as diamond-like carbon (DLC), titanium, and titanium nitride, seem to be good candidates for future blood-contact applications. These materials were deposited as thin films by the hybrid pulsed laser deposition (PLD) technique to examine the influence of such surfaces on cell behavior. The biomaterial examinations were performed in static conditions with red blood cells and then subjected to a dynamical test to observe the cell detachment kinetics. The tests revealed differences in behavior with respect to the applied coating material. The strongest cell-biomaterial interaction was observed for the carbon-based materials compared to the titanium and titanium nitride. Among many tests, a radial flow interaction analysis gives the opportunity to analyze cell adhesion to the applied material with the high accuracy. Analysis of concentrates helped to select materials for further dynamic tests on blood using an aortic flow simulator. In this case, the platelet adhesion to the surface and their degree of activation was analyzed. The quality of the selected coating was tested using a scratch test. The analyses of the microstructure were done using high resolution transmission electron microscopy. The phase composition and the residual stress were analyzed using X-ray diffraction methods.
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
The work was related to the development of novel methods in designing and fabrication of thin, porous, tissue-like coatings. The surface modification was designed to create an environment for the appropriate cell growth. The originally designed system was established to prepare porous, synthetic coatings. The dedicated software was elaborated to control the sequential coating deposition based on the electrostatic interaction. The finite elements method (FEM) was used to determine structural and mechanical properties of the coatings. The numerical model was verified experimentally. The performed simulation predicted the coating stabilization by the graphene nanoparticles. Graphene was introduced as a stabilizer of the polymer coating. The elaborated automatic system allowed preparation the porous coatings, repetitively. Coatings were stabilized by the cross-linking chemical reaction using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide and N-hydroxysuccinimide. Nanoparticles were introduced by means of the electrostatic interaction. Mechanical analysis revealed an influence of the porous structure modification on the coating stiffness. Dynamic tests on blood subjected to the aortic flow showed antithrombogenic properties of the elaborated coatings.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.