20.500.12556/RUL-177186 Incorporation and diffusion of nitrogenous organic compounds into hydrogels for controlled release into liquid growth media Vgrajevanje dušikovih organskih spojin v hidrogele in nadzorovano sproščanje v tekoča gojišča V magistrskem delu smo razvili in optimirali alginatne hidrogele za vgrajevanje ter nadzorovano sproščanje hranil, pri čemer smo uporabili metodo postopnega notranjega premreževanja s kalcijevim karbonatom in glukono-delta-laktonom. Glavni cilj je bil pripraviti hidrogel za hrambo visokih koncentracij hranil in njihovo postopno sproščanje v osiromašeno gojišče skozi daljše časovno obdobje. V eksperimentalnem delu smo sistematično testirali različne koncentracije alginata, CaCO3 in GDL ter določili optimalno sestavo (1 % alginata, 0,15 % CaCO3, 1,1 % GDL (w/v)), ki je zagotavljala časovno ustrezno premreževanje, mehansko stabilnost in homogenost gela. Ugotovili smo, da je mogoče v hidrogel uspešno vključiti do 15 % (w/v) L-cisteina ali MES, pri čemer je bila porazdelitev hranila enakomerna, sproščanje pa nadzorovano (npr. pri L- cisteinu povprečno 135 mg/h pri vhodni koncentraciji 150 g/l). Pri višjih koncentracijah hranil (30 % w/v) so se pojavile težave z neenakomerno porazdelitvijo v hidrogelu. S primerjavo šaržnih in pretočnih režimov smo prikazali, da pretočni sistemi omogočajo počasnejše in bolj enakomerno sproščanje hranil, pri čemer je bilo v podaljšanem eksperimentu z večjim volumnom po 35 urah doseženo približno 90 % sproščanje L- cisteina. Preostanek hranila je ostal vezan v hidrogelu, kar nakazuje tudi FTIR analiza. Rezultati kažejo na velik potencial optimiranih alginatnih hidrogelov za uporabo v mikrobnih gorivnih celicah kot trajnostnih energetskih sistemih in drugih aplikacijah, kjer je potrebno postopno in dolgotrajno obtakanje oziroma dovajanje hranil. Delo daje vpogled v obnašanje sproščanja hranil ter podaja izhodišča, ki lahko služijo kot osnova za nadaljnje razumevanje in raziskave na področju biomaterialov. This master’s thesis investigates development and optimization of alginate hydrogels for entrapment and controlled release of nutrients, using gradual internal gelation with calcium carbonate and glucono-delta-lactone (GDL). The main objective was to create a hydrogel capable of incorporating high concentrations of nutrients and enabling their gradual release into minimal medium over an extended period. Various concentrations of alginate, CaCO3, and GDL, were systematically tested, subsequently determining the optimal formulation (1% alginate, 0.15% CaCO3, 1.1% GDL (w/v)) for suitable gelation times, mechanical stability, and gel homogeneity. We found that up to 15% (w/v) of L- cysteine or MES could be successfully incorporated into the hydrogel, resulting in a homogeneous distribution of the nutrient and controlled release (e.g., an average of 135 mg/h at an initial concentration of 150 g/L of L-cysteine). At higher nutrient concentrations (30% w/v), issues with inhomogeneity and poor solubility were observed. By comparing batch and flow-through systems, we demonstrated that flow- through systems can enable slower and more uniform nutrient release. During an extended experiment in larger volumes, after 35 hours approximately 90% of L-cysteine was released. The remaining nutrient was retained in the hydrogel, what was also confirmed with FT-IR analysis. Results demonstrate great potential of optimized alginate hydrogels for microbial fuel cells as sustainable energy systems, as well as other applications where gradual and long-term nutrient delivery is reqired. Together, these findings offer insight into release behavior from alginate hydrogels and outline considerations that can support further research in the field of biomaterials. alginate hydrogel internal gelation nutrient release L-cysteine MES microbial fuel cells alginatni hidrogel notranje premreževanje sproščanje hranil L-cistein MES mikrobne gorivne celice true false false Slovenski jezik Angleški jezik Magistrsko delo/naloga 2025-12-17 11:34:57 2025-12-17 11:35:02 2026-01-07 13:15:59 0000-00-00 00:00:00 2025 0 0 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 277574 263767299 55548.pdf 55548.pdf 1 D4E304C879005F2D9629542F8B727712 f230590610a9355a6b9bbec54951620a28c7e385abec5490fa6dda91e34447d1 9abca8c9-db33-11f0-9328-0050569b8976 https://repozitorij.uni-lj.si/Dokument.php?lang=slv&id=224085 Biotehniška fakulteta 0 0 0