20.500.12556/DKUM-78050 Sinteza, optimizacija in aplikacija hitozanskih in alginatnih aerogelov ter njunih kompozitov magistrsko delo Synthesis, optmization and application of chitosan and alginate aerogels and their composites Namen magistrskega dela je bil raziskati potencial aerogelov kot nosilcev za oralno dostavo aktivnih učinkovin, z željo po izboljšanju njihove biodostopnosti in doseganju kontroliranega sproščanja v prebavnih tekočinah. Aerogeli nastanejo s tvorbo gelov, v katerih se tekoča faza odstrani in nadomesti s plinasto. Perspektivni nosilci aktivnih učinkovin so zaradi svoje visokoporozne strukture, nizke gostote in velike specifične površine. V sklopu eksperimentalnega dela smo najprej s sol-gel sintezo in superkritičnim sušenjem sintetizirali aerogele. Zaradi biokompatibilnosti, biorazgradljivosti in cenovne dostopnosti smo kot izhodiščne materiale izbrali hitozan in alginat. Pridobljene hitozanske in alginatne aerogele ter njune kompozite v različnih koncentracijah smo karakterizirali s plinsko adsorpcijo, termično analizo z DSC/TGA, določanjem deleža nabrekanja in Fourierjevo transformacijsko infrardečo spektroskopijo. Karakterizacija je služila za izbor aerogelov z najboljšimi lastnostmi za impregnacijo z aktivnimi učinkovinami. Kot aktivni učinkovini smo izbrali fenofibrat in esomeprazol, ki sta slabo topna v vodnih medijih in je zato njuna absorpcija v telesu otežena. Fenofibrat se uporablja za zdravljenje hiperholesterolemije, esomeprazol pa za zmanjševanje izločanja želodčne kisline. Aktivni učinkovini smo v aerogele vezali z dvema različnima postopkoma impregnacije, s superkritično impregnacijo (SCI) in z difuzijo iz topila med sol-gel sintezo (DIF). Uspešnost vezave aktivnih učinkovin v aerogele smo izračunali preko merjenja absorbanc z UV-Vis spektrometrom. Nazadnje smo testirali sproščanje aktivnih učinkovin iz aerogelov v simuliranih tekočinah prebavnega trakta. Rezultati so pokazali uspešno vezavo aktivnih učinkovin v aerogele. Tako pri impregnaciji fenofibrata kot tudi esomeprazola v aerogele smo v primerjavi s čistimi učinkovinami dosegli izboljšano oz. bolj kontrolirano sproščanje. The aim of the master thesis was to investigate the potential of aerogels as drug carriers for oral delivery to improve the bioavailability of the selected model drugs and to achieve their controlled release in simulated gastrointestinal fluids. Aerogels are prepared by the formation of gels in which the liquid phase is removed and replaced by a gaseous phase. They are promising drug carriers due to their highly porous structure, low density and large specific surface area. The experimental work includes the production of aerogels by sol-gel synthesis and supercritical drying. Chitosan and alginate were selected as precursor materials because of their biocompatibility, biodegradability and affordability. The obtained chitosan and alginate aerogels and their composites in different concentrations were characterized by gas adsorption, thermal analysis with DSC / TGA, determination of the swelling ratio and Fourier-transform infrared spectroscopy. The characterization was used to select aerogels with the best properties for impregnation with model drugs. Fenofibrate and esomeprazole were chosen as model drugs due to their poor solubility in aqueous medias and the resulting difficult absorption in the body. Fenofibrate is used to treat hypercholesterolemia and esomeprazole to reduce gastric acid. Two different impregnation methods were chosen for loading aerogels with drugs: supercritical impregnation (SCI) and diffusion from the solvent during sol-gel synthesis (DIF). The drug loadings in aerogels were calculated by measuring the absorbances with a UV-Vis spectrometer. Finally, the drug release profiles from aerogels in simulated gastrointestinal fluids were determined. The results showed successful loading of model drugs in aerogels. By impregnation of the aerogels with fenofibrate and esomeprazole an improved and more controlled release was achieved. aerogeli polisaharidi prevleke aktivne učinkovine impregnacija sproščanje aerogels polysaccharides coatings drugs impregnation release true true false [K. A. Kravanja] Slovenski jezik Angleški jezik Magistrsko delo/naloga 2020-10-11 20:14:01 2020-11-25 12:44:30 2022-08-09 17:31:14 2020-11-28 03:29:37 2020 0 Maribor 0 Maribor X, 57 f. 0000-00-00 NiDoloceno NiDoloceno NiDoloceno 0000-00-00 0000-00-00 0000-00-00 544.774.2(043.2) 39440899 URN:SI:UM:DK:2FRKCDY3 MAG_Kravanja_Katja_Andrina_2020.pdf MAG_Kravanja_Katja_Andrina_2020.pdf 1 4CEEAC2A3B6175C24EED9E24688153A9 3affe76c9e1cb5f8510ea1f9b17923f00c4ecac1181b96ee74f1d564908f1561 02ef244a-7c12-11eb-bb7a-00155d0001ca 20.500.12556/dkum/bf7e9e95-45fa-4df4-986e-9c7fe25c4f88 https://dk.um.si/Dokument.php?lang=slv&id=147692 Fakulteta za kemijo in kemijsko tehnologijo 0 0 0