Modificiranje svojstava hidrogelova dodatkom materijala iz biogenog izvora

undergraduate thesis

• Title (english): Modifying the properties of hydrogels by adding material from a biogenic source
• Author: Jana Avgustini
• Mentor: Gordana Matijašić (mentor)
• Committee member: Gordana Matijašić (predsjednik povjerenstva)
• Committee member: Jasna Prlić Kardum (član povjerenstva)
• Committee member: Dajana Kučić Grgić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Chemical Engineering and Technology; Zagreb
• Defense date and country: 2024-07-05, Croatia
• Scientific / art field, discipline and subdiscipline: TECHNICAL SCIENCES; Chemical Engineering

Abstract

U inženjerstvu mekog tkiva stavlja se veliki naglasak na proizvodnju strukturnih nosača od biomaterijala. Oni se često proizvode od hidrogelova decelularizirane izvanstanične matrice (dECM) jer se postupkom decelularizacije uklanjaju stanice svojstvene izvornoj matrici uz očuvanje biološko-kemijskih karakteristika iste. Nosači moraju imati odgovarajuću mehaničku čvrstoću i stabilnost kako bi podupirali prianjanje, rast i razvoj stanica u čemu sam dECM često ne zadovoljava. Stoga se fizikalno-kemijska i mehanička svojstva modificiraju dodatkom prirodnih polisaharida poput natrijeva alginata. Osim toga, geliranje samog natrijeva alginata može se potaknuti dodatkom kalcijeva klorida, čime se neposredno utječe i na njegovu čvrstoću. Takvom pripremom nastaju hibridni hidrogelovi natrijeva alginata uz kalcijev klorid i dECM-a. Hidrogelovima pripremljenim od natrijeva alginata (3 % i 5 % mas.) uz dodatak kalcijeva klorida (1 – 5 i 8 % mas.) ispitivalo se reološko ponašanje i određivala viskoznost kako bi se istražio utjecaj CaCl2 na mehanička svojstva gelova. Hidrogelove pripremljene kombiniranjem različitih koncentracija natrijeva alginata uz 5% CaCl2 s dECM-om karakteriziralo se pomoću razlikovne pretražne kalorimetrije (engl. differential scanning calorimetry, DSC) te infracrvenom spektroskopijom s Fourierovom transformacijom (engl. Fourier-transform infrared spectroscopy, FTIR). Na taj način su se ispitale stabilnost i potencijalne novonastale veze u hibridnim hidrogelovima. Rezultati reoloških ispitivanja pokazali su da su hidrogelovi natrijeva alginata uz dodatak 5% kalcijeva klorida najprimjenjiviji za daljnja ispitivanja. Rezultati ispitivanja pomoću DSC-e pokazali su da je uzorak 25 dECM/75 5% ALG najstabilniji, a rezultati FTIR analize upućuju da su najčvršće veze u uzorku 50 dECM/50 3% ALG. Dakle, rezultati nisu jednoznačno uputili na uzorak koji se može smatrati najpogodnijim za buduću analizu što se često događa u ispitivanju svojstava hidrogelova. Zahtjevi za in vivo primjenu i 3D ispis često su kontradiktorni i potrebno je pomno ugađanje parametara poput viskoznosti, stupnja umrežavanja i termičkih svojstava za pripremu odgovarajućeg hidrogelnog nosača.

Abstract (english)

In soft tissue engineering, there is a great emphasis on the production of scaffolds from biomaterials. They are often produced from decellularized extracellular matrix (dECM) hydrogels because during the decellularization process native cells are removed with the preservation of biological and chemical characteristics. Scaffolds must meet certain requirements such as mechanical stiffness and stability to support cell adhesion, growth, and development, in which dECM alone frequently does not suffice. Therefore, the physico-chemical and mechanical properties are modified with the addition of natural polysaccharides such as sodium alginate. In addition, the gelation of sodium alginate itself can be stimulated by the addition of calcium chloride, which directly affects its mechanical strength. Such preparation creates hybrid hydrogels of sodium alginate with calcium chloride and dECM. To characterize the hydrogels prepared from sodium alginate (3% and 5% wt%) and calcium chloride (1-5 and 8% wt%), their rheological behaviour was examined, determining the viscosity to investigate the influence of CaCl2 on the mechanical properties of gels. Hydrogels prepared by combining different concentrations of sodium alginate with dECM were characterized using differential scanning calorimetry (DSC) and Fourier-transform infrared spectroscopy (FTIR). In this way, the stability and potential newly formed bonds in the combined hydrogels were tested. The results of rheological testing showed that sodium alginate hydrogels with 5% calcium chloride were most applicable for further testing, The results of DSC tests showed that the 25 dECM/75 3% ALG sample is the most stable, and the FTIR analysis results indicate that the strongest bonds are in the 50 dECM/50 3% ALG sample. Thus, the results did not unequivocally point to the sample that can be considered the most suitable for future analysis, which commonly happens in testing the properties of hydrogels. Requirements for in vivo application and 3D printing are often contradictory and it’s necessary to carefully adjust parameters such as viscosity, degree of crosslinking and thermal properties for preparation of the appropriate hydrogel scaffold.

• Keywords: hidrogel; izvanstanična matrica; natrijev alginat; strukturni nosač; reologija; FTIR; DSC
• Keywords (english): hydrogel; extracellular matrix; sodium alginate; scaffold; rheology; FTIR; DSC
• Language: croatian
• URN:NBN: urn:nbn:hr:149:952128
• Study programme: Title: Chemical 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: 2024-07-08 10:48:58