In vitro ispitivanje oslobađanja azitromicina iz kationskih liposoma uklopljenih u kitozanski gel

master's thesis

• Title (english): In vitro release of azithromycin from cationic liposomes incorporated into chitosan gel
• Author: Nikolina Mihaljević
• Mentor: Željka Vanić (mentor)
• Committee member: Željka Vanić (predsjednik povjerenstva)
• Committee member: Mario Jug (član povjerenstva)
• Committee member: Dubravka Vitali Čepo (član povjerenstva)
• Granter: University of Zagreb; Faculty of Pharmacy and Biochemistry; (Department of pharmaceutical technology); Zagreb
• Defense date and country: 2016-09-29, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Pharmacy; Pharmacy

Abstract

Cilj ovog rada bio je ispitati oslobađanje azitromicina iz kationskih liposoma uklopljenih u kitozanski gel. U tu svrhu pripravljene su film metodom dvije preparacije kationskih liposoma; DPPC/DODAB liposomi te SPC liposomi obloženi kitozanom, a za usporedu su poslužili negativno nabijeni SPC liposomi. Sve su formulacije karakterizirane u pogledu srednjeg promjena, indeksa polidisperznosti i zeta potencijala, prije i nakon homogenizacije disperzija korištenjem ekstrudera i ultrazvučne sonde. Nakon odijeljivanja neuklopljenog lijeka liposomi su umiješani u kitozanski gel pripravljen iz kitozana velike molekulske mase. Koncentracija liposoma u gelu bila je 30% (w/w). Srednji promjer liposoma, nakon provedene homogenizacije, kretao se između 130 (SPC liposomi) i 250 nm (DPPC/DODAB); jedino su oni obloženi kitozanom bili su nešto veći zbog specifičnosti postupka izrade. Zeta potencijali kationskih liposoma bili su veći od +30 mV, dok je za SPC liposome zeta potencijal bio manji od -30 mV, što ukazuje na fizičku stabilnost svih pripravljenih disperzija. Rezultati in vitro ispitivanja oslobađanja azitromicina iz liposoma-u-gelu ukazuju na brzi trend oslobađanja lijeka u prva 4 sata ispitivanja i polaganiji tijekom idućih 20 sati. Nije uočena statistički značajna razlika u profilu oslobađanja lijeka između ispitivanih kationskih i anionske formulacije liposoma. Usporedba s kontrolnim gelom (sadrži otopinu azitromicina umjesto liposoma), ukazuje na polaganiji trend oslobađanja azitromicina iz svih liposomskih pripravaka.

Abstract (english)

The aim of this study was to examine the release profile of azithromycin from liposomes embedded in chitosan hydrogel. For that purpose, two type of cationic liposomes were prepared by film hydration method: DPPC/DODAB liposomes and SPC liposomes coated with 0,3% (w/w) chitosan solution. Negatively charged SPC liposomes served for comparison. All liposomal preparations were physically characterized before and after homogenization by measuring mean diameter, size distribution and zeta potential. Homogenization of different liposome dispersions was preformed using an ultrasonic probe sonicator or extruder. After separation of unencapsulated drug, the liposomes were mixed into a gel prepared from high-molecular weight chitosan. The concentration of liposomes in the gel was 30% (w/w). After homogenization, the mean diameter ranged between 130 nm (SPC liposomes) and 250 nm (DPPC/DODAB). Liposomes coated with chitosan were slightly higher due to the specificities of the manufacturing process. Zeta potentials of the cationic liposomes were higher than +30 mV, while the zeta potential of the SPC liposomes was less than -30 mV, indicating the physical stability of all the prepared liposome dispersions. In vitro release results indicate a trend of rapid drug release in the first 4 hours and slower in the next 20 hours. There were no statistically significant differences in the drug release from all the tested cationic and anionic liposomes. When compared to control (gel containing solution of azithromycin instead of the liposomes), slower release of azithromycin from all the tested liposome formulations was proven.

• Keywords: kitozan; liposomi; azitromicin; in vitro oslobađanje
• Keywords (english): chitosan; liposomes; azithromycin; in vitro release
• Language: croatian
• URN:NBN: urn:nbn:hr:163:170145
• Study programme: Title: Pharmacy; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: magistar/magistra farmacije (magistar/magistra farmacije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2021-05-07 11:40:33