Molecular Excited States in Micellar Systems

Lindig, Barbara A.; Rodgers, Michael A. J.

doi:10.1111/j.1751-1097.1980.tb03756.x

Cited by 26 publications

(7 citation statements)

References 58 publications

(10 reference statements)

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“…In one set of experiments, liposomes were prepared with didodecyldimethylammonium bromide incorporating 2-acetonaphthone as the sensitizer and 1.3-diphenylisobenzofuran as an internal monitor for A . The addition of histidine to the external buffer led to an increase in the bleaching rate of this monitor, corresponding to k(A + His) = 6.7 x lo7 e/mol/s, in close correspondence to the values found in aqueous or micellar solutions (Lindig and Rodgers, 1981). In another set of experiments, the bleaching of anthracene dipropionic acid had the same first order rate constants with liposomes prepared from didodecyldimethylammonium bromide, di-noctadecyl phosphate, and egg lecithin, all photosensitized by 2-acetonaphtone.…”

Section: Hematoporphyrin Derivativesupporting

confidence: 81%

“…The average incident intensity on the 1.8 cm2 illuminated face was 100 W/m2 or 5 x 10" photonsls. The absorbed dose rate in the 3 me of (Lindig and Rodgers, 1981), the fraction of reactions with histidine was0.4, which increases the efficiency of the RNO system to 0.015. A likely factor in the remaining low efficiency is the reaction of histidine with the trans-annular peroxide formed by the reaction of A with histidine.…”

Section: Hematoporphyrin Derivativementioning

confidence: 97%

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SINGLET OXYGEN GENERATION BY HEMATOPORPHYRIN IX, UROPORPHYRIN I and HEMATOPORPHYRIN DERIVATIVE AT 546 nm IN PHOSPHATE BUFFER and IN THE PRESENCE OF EGG PHOSPHATIDYLCHOLINE LIPOSOMES

Blum

Grossweiner

1985

Photochem & Photobiology

122

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Abstract— The quantum yield of singlet oxygen generation (φ) was measured at 546 nm with the p‐nitrosodimethylaniline (RNO) method. The results obtained in pH 7.4 phosphate buffer (PB) were: φ(HP) = 0.44 ± 0.05: φ= 0.71 ± 0.07: φ(HpD‐A) = 0.06 ± 0.02. The value of φ was constant from 3 to 67 μM, attributed to the dominance of HP dimers; φ (HP) increased to 0.77 ± 0.13 in the presence of small egg phosphatidylcholine liposomes (SUV), attributed to solubilization and monomerization: φ (HpD‐A) increased to 0.87 ± 0.17 in the presence of SUV. attributed to monomerization of the impurity porphyrins and unfolding of the covalent dimer constituents. The quantum efficiency of the RNO system (100 μM RNO plus 10 mM histidine) was approximately 0.015 at pH 7.4 and increased significantly at lower pH.

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Section: Hematoporphyrin Derivativesupporting

confidence: 81%

Section: Hematoporphyrin Derivativementioning

confidence: 97%

SINGLET OXYGEN GENERATION BY HEMATOPORPHYRIN IX, UROPORPHYRIN I and HEMATOPORPHYRIN DERIVATIVE AT 546 nm IN PHOSPHATE BUFFER and IN THE PRESENCE OF EGG PHOSPHATIDYLCHOLINE LIPOSOMES

Blum

Grossweiner

1985

Photochem & Photobiology

122

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“…Since many sensitizers are aromatic apolar molecules, it is likely that they will parallel the distribution of Ina into lipophilic regions of the membrane. This should increase their local concentration and greatly enhance the efficiency of the energy-transfer process (1,21,22).In this paper we examine whether Ina can be effectively activated to form reactive species by photosensitization using (i) donor chromophores that partition into the lipid bilayer,(ii) donor chromophores such as fluorescein isothiocyanate (FluNCS) that can be covalently attached to proteins, and (iii) intrinsic donor chromophores such as the retinal of rhodopsin. To establish whether the reactive species formed following photosensitization of Ina were equivalent to those generated by direct photolysis of Ina, we determined ( tTo whom reprint requests should be addressed.…”

mentioning

confidence: 99%

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confidence: 99%

Selective labeling of proteins in biological systems by photosensitization of 5-iodonaphthalene-1-azide.

Raviv¹,

Salomon²,

Gitler³

et al. 1987

Proc. Natl. Acad. Sci. U.S.A.

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The apolar azide of 5-iodonaphthalene-1-azide (Ina) partitions into the lipid bilayer of biological membranes. Upon photolysis at 314 nm, it is rapidly converted into the reactive nitrene, which efficiently attaches covalently to lipid-embedded domains of proteins and, to a lesser extent, to membrane phospholipids. Above 370 nm, Ina absorption is negligible and photolysis at these wavelengths does not occur. However, on addition of the photosensitizing molecule 3-aminopyrene, trifluoperazine, or 8-anilinonaphthalene-1-sulfonate, followed by irradiation at 380 nm, efficient conversion of Ina to reactive species was observed, as measured by ['251]Ina-labeling of membrane proteins and inactivation of the hormonal response of adenylate cyclase. Irradiation at 480 nm in the presence of a fluorescein derivative of n-undecylamine also resulted in a pattern of [125] Klip and Gitler (1, 2) introduced the use of highly lipid-soluble azides for the labeling of proteins in membranes. Various reagents of this type have been developed and their properties have been reviewed (3-7). 5-Iodonaphthalene-1-azide (Ina) was used frequently and proved to be efficient in labeling hydrophobic domains of membrane proteins (8-12).Ina is highly hydrophobic (partition coefficient >105) (11) and partitions efficiently into the lipid bilayer of various cellular membranes. Upon photolysis (Xmax = 310 nm, E -21,400M-1 cm-1) with the 314-nm line of a mercury lamp, it is rapidly and efficiently converted into the reactive nitrene, which inserts covalently into intrinsic membrane proteins that contain lipid-embedded domains and, to a lesser extent, into phospholipids. When photoactivated in the plasma membrane, Ina blocks transduction of hormonal stimulation of adenylate cyclase by uncoupling of the hormone receptor from the enzyme (13).It was of interest to determine whether energy-transfer processes could be used to photoactivate a discrete fraction of the azide molecules present in a membrane or cell.Resonance energy transfer could not be used because Ina absorbs light down to 260 nm and any donor molecules chosen for its photoactivation would have to have absorption maxima below this wavelength, this clearly being impractical. Aromatic azides, however, are capable of photosensitized activation by donors that absorb at longer wavelengths than those absorbed by the azides themselves (14, 15). Photosensitization occurs by various mechanisms (16, 17) in a process that requires the approach of the photosensitizer and acceptor pair to within the collisional range in order for intermolecular exchange of excitation energy to take place (18). The nature of the reactive intermediates generated by photosensitization of aryl azides in different solvents is not completely understood. However, they seem to be reactive in hydrogen-abstraction, dimerization, and insertion reactions (19,20). Since many sensitizers are aromatic apolar molecules, it is likely that they will parallel the distribution of Ina into lipophilic regions of the membrane. This sh...

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“…Fluorescence probes have been extremely useful in the study of micelles and other organized surfactant solutions. Numerous reviews on the use of fluorescence probes are available (Lindig and Rogers, 1980;Turro er al., 1980a;Thomas, 1979;Kalyanasundaram, 1978). One useful approach is the covalent incorporation of luninescent chromophores into surfactant molecules (Almgren, 1972;Nomura ef ul., 1980;Russell et ul.. 1980;Schmell and Whitten, 1980;Turro and Schore, 1975;Turro er a/., 1980b).…”

Section: Introductionmentioning

confidence: 99%

New Probes for Surfactant Solutions: Phosphorescent Labelled Detergents

Bolt

Turrot

2008

Photochemistry and Photobiology

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Abstract— A series of alkyltrimethylammonium bromides containing terminal phosphorescent chromo‐phores have been prepared and characterized. 10‐(4‐bromo, l‐naphthoyl)decyltrimethylammonium bromide(BND–10) has a critical micelle concentration (CMC) of 14 mM and a micellar mean aggregation number () of 105. Analogous detergents,BND–11, ‐8, and ‐5 have also been prepared; in each case, the naphthoyl group is located at the terminal carbon of an alkyl chain of the indicated length. The normal behavior of increasing and decreasing CMC with increasing aliphatic chain length is observed. When compared with unsubstituted alkyltrimethylammonium bromides, the 4‐bromo, 1‐naphthoyl chromo‐phore is roughly equivalent to 6 methylenes with respect to hydrophobic contribution. A broad phosphorescence maximizing at about 590 nm is readily detected upon photoexcitation of the BND molecules in various solvents. The weak fluorescence of the probes is consistent with efficient intersystem crossing of the BND molecules. BND–10 has a phosphorescence yield of 0.023 and a lifetime of 1 ms in water at 250C. The probes are useful for the study of micelle‐detergent exchange dynamics.

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Molecular Excited States in Micellar Systems

Cited by 26 publications

References 58 publications

SINGLET OXYGEN GENERATION BY HEMATOPORPHYRIN IX, UROPORPHYRIN I and HEMATOPORPHYRIN DERIVATIVE AT 546 nm IN PHOSPHATE BUFFER and IN THE PRESENCE OF EGG PHOSPHATIDYLCHOLINE LIPOSOMES

SINGLET OXYGEN GENERATION BY HEMATOPORPHYRIN IX, UROPORPHYRIN I and HEMATOPORPHYRIN DERIVATIVE AT 546 nm IN PHOSPHATE BUFFER and IN THE PRESENCE OF EGG PHOSPHATIDYLCHOLINE LIPOSOMES

Selective labeling of proteins in biological systems by photosensitization of 5-iodonaphthalene-1-azide.

New Probes for Surfactant Solutions: Phosphorescent Labelled Detergents

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