Karakterizacija strukturnih obilježja valovite faze fosfokolinskoh liposoma FT-IR spektroskopijom

master's thesis

• Title (english): Characterization of the structural features of ripple phase of phosphocholine liposomes using FT-IR spectroscopy
• Author: Marina Pišonić
• Mentor: Danijela Bakarić (mentor)
• Committee member: Snežana Miljanić (predsjednik povjerenstva)
• Committee member: Željka Soldin (član povjerenstva)
• Committee member: Vesna Petrović Peroković (član povjerenstva)
• Committee member: Adriana Kenđel (član povjerenstva)
• Granter: University of Zagreb; Faculty of Science; (Department of Chemistry); Zagreb
• Defense date and country: 2021-09-30, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Chemistry

Abstract

Molekule 1,2-dipalmitoil-sn-glicero-3-fosfokolina (engl. 1,2-dipalmitoyl-sn-glicero-3-
phosphatidylcholine, DPPC) u vodenom mediju stvaraju hidrirane dvosloje koji se, ovisno o
temperaturi, nalaze u određenoj fazi. Prijelaz DPPC-a iz faze gela (Lβ') u fazu fluida (Lα),
odnosno glavni fazni prijelaz opažen pri temperaturi mekšanja (Tm), prekinut je valovitom
fazom (Pβ') koja se opaža pri temperaturi pretprijelaza (Tp). Budući da su Tm i Tp iznimno
osjetljive na ugradnju organskih molekula u lipidni dvosloj, posebice onih koje su kadre
primati i otpuštati proton, u sklopu ovog diplomskog rada istraženi su višestruki hidrirani
dvosloji DPPC lipida u odsutnosti i prisutnosti male količine palmitinske kiseline (engl.
palmitic acid, PA) u puferima različitih pH vrijednosti. Tm i Tp određene su analizom
vibracijskih potpisa metilenskih (νsCH2) i fosfatnih (νasPO2−) skupina iz temperaturno-ovisnih
FT-IR spektara. Dobiveni podaci su djelomično upotpunjeni onima dobivenima iz
razlikovno-pretražne kalorimetrije (engl. differential scanning calorimetry, DSC).

Abstract (english)

1,2-dipalmitoyl-sn-glycero-3-phosphocoline form hydrated bilayers in an aqueous medium
which, depending on the temperature, can be found in certain phase. The transition from gel
(Lβ') to fluid phase (Lα), assigned as the main phase transition with a peak at melting point
temperature (Tm), is interrupted by the ripple phase (Pβ') observed at the pretransition
temeprature (Tp). Since Tm and Tp are extremely sensitive to the incorporation of organic
molecules into the lipid bilayer, especially those capable of receiving and releasing a proton,
multiple hydrated bilayers of DPPC lipids in the absence and presence of small amounts of
palmitic acid (PA) in buffers of different pH values have been investigated across this thesis.
Tm and Tp have been determined by the analysis of vibrational signatures of methylene
(νsCH2) and phosphate (νasPO2−) groups from temperature-dependent FT-IR spectra. These
data have been partially supplemented by those obtained from differential scanning
calorimetry (DSC).

• Keywords: DSC; fazni prijelaz; fosfokolin; FT-IR; valovita faza
• Keywords (english): DSC; FT-IR; phosphocholine; phase transiton; ripple phase
• Language: croatian
• URN:NBN: urn:nbn:hr:217:739690
• Project: Number: UIP-2014-09-6090; Title: Molekularni aspekti oksidativnih procesa u stanicama; Title: Molecular Aspects of Oxidative Processes in Cells; Acronym: MolOxStress; Leader: Mario Vazdar; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: UIP
• Project: Number: IP-2019-04-3804; Title: Prijenos tvari kroz biološke membrane potpomognut proteinima; Title: Protein Assisted Translocation of Matter across Biological Membranes; Acronym: ProtBioMemb; Leader: Mario Vazdar; Jurisdiction: Croatia; Funder: HRZZ; Funding stream: IP
• Study programme: Title: Graduate university studies in chemistry; specializations in: Research programme; Course: Research programme; Study programme type: university; Study level: graduate; Academic / professional title: magistar/magistra kemije (magistar/magistra kemije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access; Embargo expiration date: 2023-09-30
• Created on: 2021-10-26 14:00:41