Utjecaj bioaktivnog stakla na svojstva kompozitnih mikrosfera

undergraduate thesis

• Title (english): Influence of bioactive glass on properties of composite microspheres
• Author: Lora Marić
• Mentor: Marica Ivanković (mentor)
• Committee member: Marica Ivanković (predsjednik povjerenstva)
• Committee member: Anamarija Rogina (član povjerenstva)
• Committee member: Leonard Bauer (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2023-09-12, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

Kitozan, linearni polisaharid koji se može dobiti djelomičnom deacetilacijom prirodnog polimera hitina, odlikuje se izuzetnim fizikalno-kemijskim svojstvima poput biorazgradljivosti i biokompatibilnosti. Osim proučavanja keliranja s metalnim ionima do danas je mali broj istraživanja proveden s ciljem povezivanja kitozana s drugim komponentama. Cilj ovoga rada je priprava kompozitnih mikrosfera na temelju kitozana, Cu2+ iona i bioaktivnog stakla metodom elektroštrcanja. Pretražnim optičkim fluorescentnim i pretražnim elektronskim mikroskopom, rendgenskom analizom i infracrvenom spektroskopijom ispitan je utjecaj različitog udjela bakrovih (II) iona i bioaktivnog stakla na veličinu, oblik, morfologiju te sastav kitozanskih mikrosfera. Nađeno je da je površina mikrosfera naborana, neporozna i uglavnom sferična za sve uzorke osim za one s najmanjim ispitanim udjelom Cu2+ iona. Dodatkom bioaktivnog stakla na površini kompozitnih mikrosfera uočene su izbočine za koje je detekcija atoma SEM-EDS metodom potvrdila da su čestice biostakla. Raspodjela veličina čestica seže od 38 μm do 60 μm i ovisi o sastavu. Povećanjem udjela Cu2+ iona i povećanjem udjela bioaktivnog stakla mikrosfere imaju sve uniformniju raspodjelu i interval raspodjele veličine čestica se znatno sužava. FTIR spektri pokazuju da dodatak metalnog iona dovodi do neznatne razlike u položaju vrpci koje odgovaraju vibracijama O-H i N-H veza, iz čega se zaključuje kako na tim skupinama dolazi do povezivanja kitozana i bakra. Dodatkom bioaktivnog stakla ne uočavaju se značajnije razlike. Difrakcijska slika kitozana ne mijenja se uz Cu2+ ione, što potvrđuje stvaranje kompleksa, a pojavljuje se novi difrakcijski maksimum karakterističan za bioaktivno staklo. Primjenom metode elektroštrcanja uz kontroliranu promjenu udjela bakra i bioaktivnog stakla može se utjecati na morfologiju i raspodjelu veličine kompozitnih mikrosfera na temelju kitozana.

Abstract (english)

Chitosan, a linear polysaccharide that can be obtained by partial deacetylation of the natural polymer chitin, possesses exceptional physicochemical properties, including biodegradability and biocompatibility. Apart from the study of chelation with metal ions, there is a small amount of research based on chitosan's connection to other components. The aim of this work is to prepare composite microspheres based on chitosan, Cu2+ ions and bioactive glass using an electrospraying method. The influence of different proportions of copper (II) ions and bioactive glass on the size, shape, morphology and composition of chitosan microspheres was investigated using scanning optical fluorescence and scanning electron microscopy, X-ray analysis and infrared spectroscopy. The surface of the microspheres is wrinkled, non-porous and mostly spherical for all samples except those with the smallest investigated proportion of Cu2+ ions. Upon introducing bioactive glass, noticeable protrusions are observed on the surface of the composite microspheres, which are confirmed by SEM-EDS atomic detection to be bioglass particles. The distribution of particle sizes ranges from 38 μm to 60 μm depending on the composition of each sample. With the increase of Cu2+ ion and bioglass content, the microspheres have a more uniform size distribution and the interval of particle size distribution narrows significantl. FTIR spectra show that the addition of the metal ion leads to a minor difference in the position of the bands corresponding to the O-H and N-H bond vibrations, indicating the interaction between chitosan and copper in these functional groups. Conversely, no significant differences are observed with the addition of bioactive glass. Likewise, the diffraction pattern of chitosan does not change with Cu2+ ions, which confirms the formation of a complex, while a new diffraction maximum characteristic for bioactive glass appears. The morphology and size distribution of composite chitosan-based microspheres obtained by electrospraying method can be controlled with the amount of cupric ions and bioactive glass.

• Keywords: kitozan; mikrosfere; bakrovi (II) ioni; bioaktivno staklo; elektroštrcanje
• Keywords (english): chitosan; microspheres; cupric ions; bioactive glass; electrospray
• Language: croatian
• URN:NBN: urn:nbn:hr:149:936733
• Study programme: Title: Materials Science and Engineering - Undergraduate study; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva (sveučilišni/a prvostupnik/ prvostupnica (baccalaureus/baccalaurea) inženjer/inženjerka kemijskog inženjerstva)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-09-14 10:23:40