Priprava i karakterizacija supstituiranog hidroksiapatita

master's thesis

• Title (english): Preparation and characterisation of substituted hydroxyapatite
• Author: Dominik Horvat
• Mentor: Marica Ivanković (mentor)
• Committee member: Marica Ivanković (predsjednik povjerenstva)
• Committee member: Nevenka Vrbos (član povjerenstva)
• Committee member: Hrvoje Ivanković (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2020-09-29, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Cilj ovog rada bio je provedba hidrotermalne sinteze hidroksiapatita (Ca10(PO4)6(OH)2, HAp) iz sipine kosti uz prisustvo metalnih iona stroncija (Sr2+) te karakterizacija uzoraka različitim instrumentalnim metodama (XRD, FTIR i TGA) kako bi se procijenila uspješnost ugradnje iona u strukturu hidroksiapatita. Ionske supstitucije utječu na različite parametre poput veličine kristalne rešetke, veličine kristalita ili morfologije što se odražava u promjeni svojstava HAp-a, a samim time i u primjenskim svojstvima za upotrebu u inženjerstvu koštanog tkiva. SEM analizom potvrđeno je očuvanje karakteristične visokoporozne međusobno povezane strukture sipine kosti nakon provedbe hidrotermalne sinteze. Kvalitativnom XRD analizom utvrđeno je da se sintetizirani uzorci sastoje od HAp-a i male količine aragonitne faze (1-2 %) kod uzoraka s 5 i 10 mol.% dodanog stroncija. Dodatnom obradom podataka pomoću Rietveldove metode utočnjavanja dobiveno je da se volumen kristalne rešetke HAp-a povećava s povećanjem udjela stroncija što je u skladu s teorijskim i literaturnim podacima. Rezultati dobiveni FTIR analizom ukazuju na smanjenje intenziteta fosfatnih, karbonatnih i hidroksilnih skupina s povećanjem udjela dodanog stroncija. Dodatkom stroncija ne dolazi do širenja vrpca pojedinih skupina nego zadržavaju svoj početni oblik. Primjenom TGA analize utvrđeno je da se pri manjim udjelima stroncija termička stabilnost poboljšava, no kod viših udjela stroncija gubitak mase se povećava u odnosu na čisti HAp.

Abstract (english)

The aim of this work was to conduct the hydrothermal synthesis of hydroxyapatite from cuttlebone with the presence of strontium ions (Sr2+) and the subsequent characterization of the samples using different instrumental methods (XRD, FTIR and TGA) to assess the substitution of ions in the structure of hydroxyapatite. Ionic substitutions affect different parameters like crystal cell, crystal size and morphology which change the properties of HAp and subsequently affect the applicability in bone tissue engineering. SEM analysis confirmed that characteristic highly porous interconnected structure of cuttlebone was preserved after hydrothermal synthesis. Qualitative XRD analysis showed that the structure of the synthesized samples consists of HAp with trace amounts of aragonite phase (1-2 %) in samples with 5 and 10 mol.% strontium added. Further processing of the data using the Rietveld refinement method showed that the volume of the crystal lattice of HAp increases with increasing strontium content, which is consistent with theoretical and literature data. The results obtained by FTIR analysis indicate a decrease in the intensity of phosphate, carbonate and hydroxyl groups with the increase of added strontium. With the addition of strontium, the bands of individual groups do not broad, but retain their initial shape. Using TGA analysis, it was found that at lower strontium content, thermal stability improves, but at higher strontium content, the weight loss increases compared to pure HAp.

• Keywords: hidrotermalna sinteza; hidroksiapatit; sipina kost; supstitucija; stroncij
• Keywords (english): hydrothermal synthesis; hydroxyapatite; cuttlebone; substitution; strontium
• Language: croatian
• URN:NBN: urn:nbn:hr:149:749584
• Project: Number: IP-2014-09-3752; Title: Razvoj biokompatibilnih materijala na temelju hidroksiapatita za primjene u inženjerstvu koštanog tkiva; Title: Development of Biocompatible Hydroxyapatite Based Materials for Bone Tissue Engineering Applications; Acronym: HaTEA; Leader: Hrvoje Ivanković; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Materials Science and Engineering - Graduate study; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra inženjer/inženjerka kemijskog inženjerstva (magistar/magistra inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Access restricted to students and staff of home institution
• Created on: 2022-03-03 09:28:16