Lipophilic dye probes are widely used for labelling of cells, organelles, liposomes, viruses and lipoproteins. The lipophilic dye diffuses in the membrane and stains the cell and cells even tolerate the lipophilic dye in high concentration. The fluorescence of styryl dyes increases after insertion into the hydrophobic environment of the lipid membrane compared their fluorescence in the aqueous phase solution. The alkyl chains of the fluorescent styryl dye probe insert into membranes and are used to understand their biophysical properties and their behavior in lipid bilayers. The mechanism of incorporation of the dyes into cell membranes, or vesicle model systems, is not resolved. In this study we used a modified dialkylaminostyryl fluorescent lipid, 4-(4-(dihexadecylamino)styryl)-N-methylpyridinium iodide (DiA), replacing the I- counterion with the Cl- anion to make DiA-Cl increase hydration of the polar head and to enable self-assembling in water and formation of vesicles. Vesicles composed of DMPC (1,2-dimyristoyl-sn-glycero-3-phosphatidylcholine)/DiA, DPPC (1,2-dipalmitoyl-sn-glycero-3- phosphatidylcholine) /DiA, DSPC (1,2-distearoyl-sn-glycero-3- phosphatidylcholine) /DiA, DMPE (1,2-dimyristoyl-sn-glycero-3-phosphoethanolamine)/DiA, DPPE (1,2-dipalmitoyl-sn-glycero-3-phosphoethanolamine)/DiA and DSPE (1,2-distearoyl-sn-glycero-3-phosphoethanolamine)/DiA have been prepared in mole ratios between 100/0 to 0/100, in order to investigate the effects of chain length and headgroup type on chain packing and phase separation in these mixed amphiphilic systems, using nanocalorimetry, dynamic light scattering and fluorescence data, as well as confocal laser scanning microscopy (CLSM) and cryo-transmission electron microscopy (Cryo-TEM). In addition, we report the self-assembly of DiA-Cl, to form H-aggregates of lipid bilayers in aqueous solution, beyond a critical vesicle concentration. Lipid bilayers can be fused onto silica nanoparticles (NPs) to form supported lipid bilayer (SLB)-NPs. (SLB)-NPs have a varous interdisciplinary applications from medicine to environmental fields and agriculture sciences. Here, the lipids on the nanoparticles were used for two applications. One was to adsorb polycyclic aromatic hydrocarbons (PAHs) from the environment and the other was as vehicles for foliar delivery of nutrients to plants. Silica SLB nanoparticles can increase the solubility of Benzo[a]Pyrene (BaP) in order to extract the BaP from soil for in situ biodegradation. Initial studies were begun on the effect of foliar application of silica SLBs nanoparticles on plants. The SLBs to be used were prepared using both 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and DiA, in order to determine whether the lipid increased the entry of the silica into the plant leaves and whether the lipids also entered. / Chemistry
| Identifer | oai:union.ndltd.org:TEMPLE/oai:scholarshare.temple.edu:20.500.12613/611 |
| Date | January 2019 |
| Creators | Bandegi, Sanaz |
| Contributors | Wunder, Stephanie L., Valentine, Ann M., Strongin, Daniel R., Ilies, Marc A. |
| Publisher | Temple University. Libraries |
| Source Sets | Temple University |
| Language | English |
| Detected Language | English |
| Type | Thesis/Dissertation, Text |
| Format | 210 pages |
| Rights | IN COPYRIGHT- This Rights Statement can be used for an Item that is in copyright. Using this statement implies that the organization making this Item available has determined that the Item is in copyright and either is the rights-holder, has obtained permission from the rights-holder(s) to make their Work(s) available, or makes the Item available under an exception or limitation to copyright (including Fair Use) that entitles it to make the Item available., http://rightsstatements.org/vocab/InC/1.0/ |
| Relation | http://dx.doi.org/10.34944/dspace/593, Theses and Dissertations |
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