Biomaterial Database

Flavonols--new fluorescent membrane probes for studying the interdigitation of lipid bilayers. 1998

O P Bondar, and V G Pivovarenko, and E S Rowe

Department of Biochemistry and Molecular Biology, University of Kansas Medical Center, Kansas City 66103, USA.

Two flavonols, 3-hydroxy-4'-dimethylaminoflavone (FME) and 3-hydroxy-4'-(15-azacrown-5) flavone (FRC) have been investigated as new fluorescence probes for studying the formation of the interdigitated gel phase in lipid bilayers. The formation of the interdigitated gel phase in the saturated symmetrical phosphatidylcholines (PCs) and phosphatidylethanol (Peth) in the presence of ethanol has been well studied. The present study examines the behavior of these new probes in PC-ethanol and Peth-ethanol systems, as well as in PC-cholesterol and Peth-cholesterol vesicles. The present results demonstrate that both flavonols give distinctively different spectra in interdigitated lipid compared to non-interdigitated lipids, when examined in lipids in which the interdigitation behavior is known. This makes them useful for determinations of the structural state of unknown lipids, and for following the transitions between interdigitated and non-interdigitated phases. However, in the presence of cholesterol, only FCR gave appropriate indications of interdigitation. The results with FME in the presence of cholesterol were not consistent with the known behavior of the lipids examined; instead, FME appears to be located preferentially in the cholesterol-rich non-interdigitated regions of the bilayer.

UI	MeSH Term	Description	Entries
D008051	Lipid Bilayers	Layers of lipid molecules which are two molecules thick. Bilayer systems are frequently studied as models of biological membranes.	Bilayers, Lipid,Bilayer, Lipid,Lipid Bilayer
D002784	Cholesterol	The principal sterol of all higher animals, distributed in body tissues, especially the brain and spinal cord, and in animal fats and oils.	Epicholesterol
D005419	Flavonoids	A group of phenyl benzopyrans named for having structures like FLAVONES.	2-Phenyl-Benzopyran,2-Phenyl-Chromene,Bioflavonoid,Bioflavonoids,Flavonoid,2-Phenyl-Benzopyrans,2-Phenyl-Chromenes,2 Phenyl Benzopyran,2 Phenyl Benzopyrans,2 Phenyl Chromene,2 Phenyl Chromenes
D005453	Fluorescence	The property of emitting radiation while being irradiated. The radiation emitted is usually of longer wavelength than that incident or absorbed, e.g., a substance can be irradiated with invisible radiation and emit visible light. X-ray fluorescence is used in diagnosis.
D005456	Fluorescent Dyes	Chemicals that emit light after excitation by light. The wave length of the emitted light is usually longer than that of the incident light. Fluorochromes are substances that cause fluorescence in other substances, i.e., dyes used to mark or label other compounds with fluorescent tags.	Flourescent Agent,Fluorescent Dye,Fluorescent Probe,Fluorescent Probes,Fluorochrome,Fluorochromes,Fluorogenic Substrates,Fluorescence Agents,Fluorescent Agents,Fluorogenic Substrate,Agents, Fluorescence,Agents, Fluorescent,Dyes, Fluorescent,Probes, Fluorescent,Substrates, Fluorogenic
D044948	Flavonols	A group of 3-hydroxy-4-keto-FLAVONOIDS.	2-Phenyl-3-Hydroxy-Benzopyran-4-Ones,3-hydroxy-4-keto-Flavonoids,2 Phenyl 3 Hydroxy Benzopyran 4 Ones,3 hydroxy 4 keto Flavonoids