Persistent Link:
http://hdl.handle.net/10150/185929
Title:
Supramolecular assemblies of polymerizable phospholipids.
Author:
Lee, Youn-Sik.
Issue Date:
1992
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Novel polymerizable ether lipids, 1,2-O-bis[10-(2',4'-hexadienoyloxy)decyl]-rac, 1,2-O-bis(10,12-tricosadiynyl)-rac, and (S)-2,3-O-bis(10,12-tricosadiynyl)-sn-glycero-1-phosphocholine (PC), were successfully synthesized. Differential scanning calorimetry (DSC) showed that the gel to liquid crystalline phase transition of the ether lipid bilayers occurs at 11.4, 27.6, and 30.0°C (T(m)), respectively. The T(m) of the saturated analogs of the sorbyl ether and ester lipids, which were synthesized for the study of lipid phase behavior, were -15.4 and -7.5°C, respectively. The sorbyl and diacetylenic ether lipids in bilayers were readily polymerized with 254 nm light. The stability of sorbyl either lipid vesicles toward a detergent, Triton X-100, was somewhat enhanced by photopolymerization. The optically active diacetylenic ether lipid formed microtubules and helices which were observed by transmission electron and optical microscopy. Polymerizable ester lipids, 1-palmitoyl-2-(2-methylene)palmitoyl, 1,2-bis(2-methylenepalmitoyl), and 1-oleoyl-2-(2-methylene)palmitoyl PC were synthesized. The T(m) of these lipids were estimated to be 33.6, 25.3, and ∼-10°C, respectively, via DSC and X-ray diffraction. Thermal reaction of the mono-substituted lipid suspensions with a water-soluble initiator, azobis(2-amidinopropane) dihydrochloride (AAPD), yielded oligomers which were soluble in organic solvents. However, reaction of the bis-substituted ester lipid in bilayers produced cross-linked polymers which are not soluble in organic solvents. The ceiling temperature for the radical polymerization of these lipid systems appears to be near 70°C since the polymerization conversion at 60°C was greater than at 70°C. Finally, a polymerizable ester lipid, 1-oleoyl-2-(2-methylene)palmitoyl-sn-glycerol-3-phosphoethanolamine (PE) was synthesized. According to DSC and X-ray diffraction, this hydrated PE suspension undergoes the transition from the lamellar liquid crystalline to the nonlamellar inverted hexagonal (H(II)) phase at 45-50°C. This compound (T(m) = 11.6°C) is a promising candidate for future studies of the stabilization of the H(II) phase.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Dissertations, Academic.; Chemistry, Organic.
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Chemistry; Graduate College
Degree Grantor:
University of Arizona
Committee Chair:
O'Brien, David F.

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleSupramolecular assemblies of polymerizable phospholipids.en_US
dc.creatorLee, Youn-Sik.en_US
dc.contributor.authorLee, Youn-Sik.en_US
dc.date.issued1992en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractNovel polymerizable ether lipids, 1,2-O-bis[10-(2',4'-hexadienoyloxy)decyl]-rac, 1,2-O-bis(10,12-tricosadiynyl)-rac, and (S)-2,3-O-bis(10,12-tricosadiynyl)-sn-glycero-1-phosphocholine (PC), were successfully synthesized. Differential scanning calorimetry (DSC) showed that the gel to liquid crystalline phase transition of the ether lipid bilayers occurs at 11.4, 27.6, and 30.0°C (T(m)), respectively. The T(m) of the saturated analogs of the sorbyl ether and ester lipids, which were synthesized for the study of lipid phase behavior, were -15.4 and -7.5°C, respectively. The sorbyl and diacetylenic ether lipids in bilayers were readily polymerized with 254 nm light. The stability of sorbyl either lipid vesicles toward a detergent, Triton X-100, was somewhat enhanced by photopolymerization. The optically active diacetylenic ether lipid formed microtubules and helices which were observed by transmission electron and optical microscopy. Polymerizable ester lipids, 1-palmitoyl-2-(2-methylene)palmitoyl, 1,2-bis(2-methylenepalmitoyl), and 1-oleoyl-2-(2-methylene)palmitoyl PC were synthesized. The T(m) of these lipids were estimated to be 33.6, 25.3, and ∼-10°C, respectively, via DSC and X-ray diffraction. Thermal reaction of the mono-substituted lipid suspensions with a water-soluble initiator, azobis(2-amidinopropane) dihydrochloride (AAPD), yielded oligomers which were soluble in organic solvents. However, reaction of the bis-substituted ester lipid in bilayers produced cross-linked polymers which are not soluble in organic solvents. The ceiling temperature for the radical polymerization of these lipid systems appears to be near 70°C since the polymerization conversion at 60°C was greater than at 70°C. Finally, a polymerizable ester lipid, 1-oleoyl-2-(2-methylene)palmitoyl-sn-glycerol-3-phosphoethanolamine (PE) was synthesized. According to DSC and X-ray diffraction, this hydrated PE suspension undergoes the transition from the lamellar liquid crystalline to the nonlamellar inverted hexagonal (H(II)) phase at 45-50°C. This compound (T(m) = 11.6°C) is a promising candidate for future studies of the stabilization of the H(II) phase.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectDissertations, Academic.en_US
dc.subjectChemistry, Organic.en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplineChemistryen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.contributor.chairO'Brien, David F.en_US
dc.contributor.committeememberMulvaney, James E.en_US
dc.contributor.committeememberMash, Eugene A., Jr.en_US
dc.contributor.committeememberVemulapalli, G. Krishnaen_US
dc.contributor.committeememberMiller, Walter B.en_US
dc.identifier.proquest9238533en_US
dc.identifier.oclc713041921en_US
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