Využití metod rozptylu světla pro studium gelace hydrogelu
Loading...
Date
Authors
ORCID
Advisor
Referee
Mark
B
Journal Title
Journal ISSN
Volume Title
Publisher
Vysoké učení technické v Brně. Fakulta chemická
Abstract
Táto bakalárska práca je zameraná na štúdium gelácie hydrogélov pomocou využitia metód rozptylu svetla. Pre tieto účely boli v práci zvolené dva biopolyméry (agaróza a alginát sodný), u ktorých prebieha gelácia rozdielnym spôsobom. V prvom prípade ide o geláciu spôsobenú zmenou teploty, v druhom potom prídavkom viazväzbového katiónu. V rámci experimentálnej časti práce bola najskôr študovaná gelácia agarózy metódou DLS, boli merané teplotné rampy roztokov agarózy (40 – 30 °C), kde boli sledované veľkosti častíc v roztokoch o rôznych koncentráciách a ich pôsobenie na meraný difúzny koeficient. Metódou DLS boli stanovené hodnoty teplôt gelácie roztokov o koncentrácii 0,5 hm.% a 1,0 hm.%. Ďalej bola použitá metóda DLS mikroreológie, kde boli taktiež merané teplotné rampy agarózových roztokov (40 – 30 °C), z ktorých boli vyhodnotené teploty gelácie roztokov agarózy o koncentrácii 0,1 hm.% a 0,5 hm.%. V práci bola tiež používaná klasická reológia, kvôli vzájomnému porovnaniu viskoelastického chovania látok a zisteniu bodu gelácie roztokov agarózy. Touto metódou boli zistené teploty gelácie pre koncentrácie 0,1 hm.%, 0,5 hm.% a 1,0 hm.%. Metóda DLS bola použitá aj k sledovaniu interakcií alginátu sodného pri prídavku Ca2+ iónov, tieto interakcie boli následne tiež vyhodnotené a diskutované v experimentálnej časti.
This bachelor thesis focuses on the study of hydrogel gelation using light scattering methods. For these purposes two different biopolymers (agarose and sodium alginate), with different sol to gelation phase transition, were selected. In the case of agarose, the gelation is caused by temperature change. On the other side, the gelation of sodium alginate is initiated by addition of polyvalent cations. In the experimental part of the work, agarose gelation was studied by DLS, temperature gradients of agarose solutions (40 – 30 °C) were measured. During the measurement the particle size distributions in the solutions having different concentrations were monitored as well as the temperature influence on the diffusion coefficient. The DLS method provided the values of the gelling temperatures of the solutions at a concentration of 0,5 wt.% and 1,0 wt.%. Furthermore, the DLS microrheology method was used, where temperature dependences of viscoelastic characteristics of agarose solutions (40 – 30 °C) were also measured, from which the gelling temperatures of agarose solutions of 0,1 wt.% and 0,5 wt.% were evaluated. The classical rheology was also used in the work to compare the viscoelastic behaviour of the samples and to determine the gelation point of the agarose solutions. By this method were determined gelling temperatures for all studied concentration of agarose (0,1 wt.%, 0,5 wt.% and 1,0 wt.%). The DLS method was also used to monitor the interactions of sodium alginate with the addition of Ca2+ ions, these interactions were then also evaluated and discussed in the experimental part.
This bachelor thesis focuses on the study of hydrogel gelation using light scattering methods. For these purposes two different biopolymers (agarose and sodium alginate), with different sol to gelation phase transition, were selected. In the case of agarose, the gelation is caused by temperature change. On the other side, the gelation of sodium alginate is initiated by addition of polyvalent cations. In the experimental part of the work, agarose gelation was studied by DLS, temperature gradients of agarose solutions (40 – 30 °C) were measured. During the measurement the particle size distributions in the solutions having different concentrations were monitored as well as the temperature influence on the diffusion coefficient. The DLS method provided the values of the gelling temperatures of the solutions at a concentration of 0,5 wt.% and 1,0 wt.%. Furthermore, the DLS microrheology method was used, where temperature dependences of viscoelastic characteristics of agarose solutions (40 – 30 °C) were also measured, from which the gelling temperatures of agarose solutions of 0,1 wt.% and 0,5 wt.% were evaluated. The classical rheology was also used in the work to compare the viscoelastic behaviour of the samples and to determine the gelation point of the agarose solutions. By this method were determined gelling temperatures for all studied concentration of agarose (0,1 wt.%, 0,5 wt.% and 1,0 wt.%). The DLS method was also used to monitor the interactions of sodium alginate with the addition of Ca2+ ions, these interactions were then also evaluated and discussed in the experimental part.
Description
Citation
CANDRÁKOVÁ, S. Využití metod rozptylu světla pro studium gelace hydrogelu [online]. Brno: Vysoké učení technické v Brně. Fakulta chemická. 2018.
Document type
Document version
Date of access to the full text
Language of document
cs
Study field
Chemie pro medicínské aplikace
Comittee
prof. Ing. Miloslav Pekař, CSc. (předseda)
prof. RNDr. Ivana Márová, CSc. (místopředseda)
doc. Ing. Petr Dzik, Ph.D. (člen)
doc. Ing. Stanislav Obruča, Ph.D. (člen)
prof. Ing. Michal Veselý, CSc. (člen)
prof. RNDr. Zbyněk Zdráhal, Dr. (člen)
Date of acceptance
2018-06-11
Defence
Pekař: Jakou metodu doporučuje jako nejvýhodnější pro stanovení bodu gelace a proč?
Co je to zeta-potenciál a jaké má toto měření vztah k vaší práci?
Jakým mechanismem byl síťovaný alginát?
Result of defence
práce byla úspěšně obhájena
Document licence
Standardní licenční smlouva - přístup k plnému textu bez omezení