An exploration into possibilities for establishing the ability of in vitro bioactivity testing of materials' surfaces

U ovom radu istražen je utjecaj površinskog stanja titanove legure Ti6Al4V ELI na njezinu bioaktivnost u simulirajućoj tjelesnoj tekućini (SBF-u). Nakon izlaganja četiriju uzoraka različitih površinskih stanja SBF-u i analize rezultata, uspoređeno je stanje površine prije i nakon provedenog ispitivanja bioaktivnosti. Ovaj rad podijeljen je na dva dijela; teoretski i eksperimentalni. Teoretski dio sadrži uvod u rad, opis SBF-a, njegove povijesti i vrsta, mehanizma djelovanja, kao i opis nastanka hidroksiapatita. U eksperimentalnom dijelu predočen je postupak istraživanja mogućnosti in vitro ispitivanja bioaktivnosti najčešće korištene titanove legure u medicinskoj primjeni. Pokus se sastojao od pripreme površina titanovih legura, pripreme SBF-a, provedbe ispitivanja bioaktivnosti u dvije iteracije SBF-a te analize stanja površina prije i poslije svakog koraka ispitivanja. Postupak pripreme površina proveden je u Laboratoriju za toplinsku obradu, dok je testiranje bioaktivnosti provedeno u Laboratoriju za analizu metala Fakulteta strojarstva i brodogradnje. Mjerenje parametara hrapavosti provedeno je u Laboratoriju za precizna mjerenja, dok je analiza površina uzoraka svjetlosnom mikroskopijom provedena u Laboratoriju za materijalografiju Fakulteta strojarstva i brodogradnje Sveučilišta u Zagrebu. Nakon provedbe eksperimenta doneseni su odgovarajući zaključci.The influence of the Ti6Al4V ELI titanium alloy’s surface state on its bioactivity in simulated body fluid (SBF) was studied in this paper. After the exposure of four samples of different surface modifications to the SBF and the subsequent analysis of the results, a comparison of the results was carried out. This paper is divided into two parts, the theoretical and the experimental part. The theoretical part contains an introduction to the paper, a description of the SBF, its history, its type and the mechanism of action, as well as the description of hydroxyapatite formation. In the experimental part, a study was carried out to investigate the possibilities for in vitro bioactivity testing. The experiment consisted of the acquisition and initial preparation of titanium alloy surfaces, SBF preparation, bioactivity testing in two SBF iterations and surface condition analysis before and after each test step. The surface preparation process was performed at the Heat Treatment Laboratory, while bioactivity testing was conducted at the Laboratory for Metal Analysis of the Faculty of Mechanical Engineering and Naval Architecture. Measurement of the roughness parameters was performed at the Laboratory for Precise Measurements, while the sample surface analysis by light microscopy was performed in the Laboratory for Materialography of the Faculty of Mechanical Engineering and Naval Architecture of the University of Zagreb. Following the implementation of the experiment, appropriate conclusions were made