High pressure impregnations of fat-soluble vitamins into polysaccharide aerogels

doctoral dissertation

Milica Pantić (Avtor), Zoran Novak (Mentor), Željko Knez (Komentor)

Povzetek

V doktorski dizertaciji smo raziskovali uporabo ogljikovega dioksida pri visokih tlakih za impregnacijo maščobo-topnih vitaminov. Za impregnacijo smo izbrali vitamina K3 in D3. Predvsem vitamin D3 je izjemno občutljiva substanca, zato zahteva izjemno pozornost. Za impregnacijo obeh vitaminov smo uporabili polisaharidne arogele. Aerogeli so porozni materiali z izjemnimi lastnostmi. Zaradi visokih poroznosti imajo velike specifične površine in nizke gostote. Če te lastnosti združimo še z biokomatibilnostjo ter biorazgradljivostjo polisaharidov, dobimo idealne materiale za farmacevtske aplikacije. Cilj doktorske dizertacije je bil impregnacija vitaminov v polisaharidne aerogele, da bi jih s tem dodatno zaščitili ter tako povišali njihovo stabilnost. Delo je razdeljeno v dva večja dela. V prvem delu smo uporabili superkritični ogljikov dioksid za impregnacijo vitamina K3 in vitamina D3. Vitamin K3 smo uporabili kot modelno substanco, naš glavni cilj pa je bil impregnacija vitamina D3. Raziskali smo termodinamske in kinetične lastnosti obeh vitaminov. Dobljene vrednosti smo razložili z uporabo že razvitih kinetičnih modelov. V prvem delu dizertacije smo določili tudi strukturne lastnosti vzorcev ter preverili sproščanje vitamina in vitro. V drugem delu doktorske dizertacije smo preiskovali impregnacijo vitamina D3 z ogljikovim dioksidom. Tokrat smo uporabili ogljikov dioksid pri različnih pogojih, od superkritičnega do tekočega ogljikovega dioksida. Preiskovali smo kinetično obnašanje pri različnih pogojih ter določili stopnjo degradacije vitamina glede na izbrane pogoje. Z različnimi karakterizacijskimi metodami smo določil vpliv tako superkritičnega kot tekočega ogljikovega dioksida na končne strukturne lastnosti aerogelov. V tem delu dizertacije smo prav tako izvedli sproščanje vitamina D3 in vitro, izvedli pa smo tudi stabilnostno študijo za potrditev povišane stabilnosti vitamina D3 ob impregnaciji v aerogele.

Ključne besede

aerogels;polysacharides;high pressure impregnation;carbon dioxide;fat soluble vitamins;vitamin K3;vitamin D3;

Podatki

Jezik:	Angleški jezik
Leto izida:	2017
Tipologija:	2.08 - Doktorska disertacija
Organizacija:	UM FKKT - Fakulteta za kemijo in kemijsko tehnologijo
Založnik:	[M. Pantić]
UDK:	604.2:547.458(043.3)
COBISS:	20538902
Št. ogledov:	1222
Št. prenosov:	186
Ocena:	0 (0 glasov)
Metapodatki:

Ostali podatki

Sekundarni jezik:	Slovenski jezik
Sekundarni naslov:	High pressure impregnations of fat-soluble vitamins into polysaccharide aerogels
Sekundarni povzetek:	This doctoral dissertation examines utilization of carbon dioxide as solvent for high pressure impregnation of fat-soluble vitamins, in particular vitamin K3 and vitamin D3. Chosen vitamins, especially vitamin D3, are handling challenging since they are highly sensitive substances. Polysaccharide alginate aerogels were used as vitamins’ carriers. Aerogels are airy materials with outstanding properties such as high porosity, high specific surface area and low density. Combined with the biocompatible and biodegradable polysaccharides, they fulfil pharmaceutical demands for ideal candidates. General idea of this dissertation was to achieve protection and prolonged stability of sensitive vitamins against environments by impregnating them into polysaccharide aerogels. The work is divided in main two parts. In the first part, carbon dioxide was used in its supercritical state. The impregnation experiments were conducted with both vitamin K3 and vitamin D3. Vitamin K3 had the role of a model substance while the main focus was on vitamin D3, as an active substance. The thermodynamic and kinetic behaviour of both vitamins was examined and fitted to appropriate models. Furthermore, detailed characterisation of the samples was applied and finally, drug release experiments were performed to examine possible application of developed products. In the second part, the study was extended from the area of supercritical carbon dioxide to the area of subcritical liquid carbon dioxide. Up now, this field was unexplored and new. The experiments were performed this time only with vitamin D3. The kinetic behaviour under various operating conditions was examined and associated with the degradation of vitamin in the system. Detailed influence of both supercritical and subcritical liquid carbon dioxide on the end structure of aerogels was investigated. Moreover, characterisation of the samples as well as drug release experiments were performed as part of the study. Finally, stability tests were carried out to investigate the protection of impregnated vitamin D3.
Sekundarne ključne besede:	aerogeli;polisaharidi;visokotlačna impregnacija;ogljikov dioksid;maščobno topni vitamini;vitamin K3;vitamin D3;doktorske disertacije;
URN:	URN:SI:UM:
Vrsta dela (COBISS):	Doktorsko delo/naloga
Komentar na gradivo:	Univ. v Mariboru, Fak. za kemijo in kemijsko tehnologijo
Strani:	XIII, 119 str.
ID:	9258150