Rationalization of the ratio of excimer-to-monomer fluorescence emission intensity in bichromophoric diesters of 1-pyrenoic acid and mono-, di-, tri-, and tetraethylene glycols

The effect of cationic, anionic and nonionic surfactants on the fluorescence properties of fluorescein and eosin Y aqueous solutions has been investigated. It has been found that sodium dodecyl sulfate does not affect the position of the maximum wavelengths of solutions of fluorescein and eosin Y in the study of the effect of an anionic surfactant on the fluorescence emission intensity of dyes. The intensity of the signal of the dye solutions when changing the concentration of anionic surfactant changes little. As the concentration of non-ionic surfactant increases, the fluorescence emission intensity of the fluorescein solutions decreases. In contrast, with increasing concentration of Triton X-100, there is an increase in the signal intensity of solutions of more hydrophobic eosin Y with subsequent access to the "plateau" at СТХ-100≥5.1·10–2 mol/L. The position of the maxima fluorescence emission wavelengths for the fluorescein solutions in the 0-1.0·10–5 mol/L range of concentrations of cationic surfactant cetylpyridinium chloride remain unchanged. The position of the maxima shifts to the long-wavelength region of the spectrum at higher concentrations of CPC. The nature of the position dependence of the fluorescence emission maxima of eosin Y solutions in the presence of cationic surfactants is similar. The effect of fluorescence quenching has also been shown in the study of the influence of organic substances of cationic nature on the signal intensity of fluorescein solutions. It has been shown that the concentration dependence is linear in the (0.1–4.0)·10–1 mol/L range of isoniazid molecule concentrations. The data obtained can be implemented in the development of conditions and methods for the determination of pharmacologically active substances of cationic nature by reaction with fluorescein in medicines.

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A study of fluorescence emission intensity of reaction products between selected amino acdis and DFO, 1,2-indanedione and 1,2-indanedione - zinc chloride

Issues of Forensic Science ◽

10.34836/pk.2014.285.2 ◽

2014 ◽

Vol 285 ◽

pp. 68-72

Author(s):

Tomasz Szczepański ◽

◽

Urszula Więckiewicz ◽

Krzysztof Klemczak ◽

Anna Chyczewska ◽

...

Keyword(s):

Amino Acids ◽

Fluorescence Intensity ◽

Zinc Chloride ◽

Emission Intensity ◽

Storage Time ◽

Spectral Characteristics ◽

Fluorescence Emission ◽

Reaction Products ◽

Intensity Measurements ◽

Fluorescence Emission Intensity

The study shows the results of fluorescence emission intensity measurements of the reaction products of selected amino acids with DFO, 1,2-IND and 1,2-IND - zinc chloride on absorptive surfaces. Conducted research addressed the following variables: type of developing reagent, type of surface, type of amino acid and sample storage time. It was confirmed that the above factors affected the fluorescence intensity of developed fingerprints. Furthermore, the studies proved that fluorescence intensity of reaction products between amino acids and 1,2- IND stored for 1 or 7 days increased for the majority of samples upon addition of zinc chloride to the developing reagent. For samples stored for 4 months the highest fluorescence emission intensity was observed for DFO. No significant differences were found in fluorescence spectral characteristics of tested compounds, depending on the type of surface.

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Spectroscopic and Fluorometric Characterization of Oxacyanine Dyes in Water and Nitrobenzene

Applied Spectroscopy ◽

10.1366/0003702884430399 ◽

1988 ◽

Vol 42 (6) ◽

pp. 958-961 ◽

Cited By ~ 5

Author(s):

Deborah H. Wiegand ◽

Petr Vanýsek

Keyword(s):

Emission Intensity ◽

Partition Coefficients ◽

Fluorescence Emission ◽

Red Shift ◽

Electrochemical Studies ◽

Interface System ◽

Fluorescence Emission Intensity ◽

20 Nm

The spectroscopic and fluorometric properties of nine oxacyanine dyes (3,3′-dimethyloxacarbocyanine through 3,3′-diheptyloxacarbocyanine, 3,3′-diethyl-, and 3,3′-dipropyloxadicarbocyanine iodides) were determined in two solvents, water and nitrobenzene. In nitrobenzene the absorbance and fluorometric spectra of the dyes showed a red shift of 15 to 20 nm when compared with the spectra in water. In addition, the fluorescence emission intensity of the dyes is lower in nitrobenzene than in water, by one to two orders of magnitude. Thus it is possible to measure fluorescence in water in water/nitrobenzene systems without interference from the nitrobenzene part. The molar absorptivities of the dyes were calculated and used to determine the solubility of the dyes in water and the partition coefficients of the dyes between nitrobenzene and water. These dyes were characterized in order to provide a better understanding of the properties of the dyes in a water/nitrobenzene interface system which will be used in electrochemical studies of the dyes.

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Liquid Chromatographic-Fluorometric Determination of Cinnamyl Alcohol in Perfumes, Colognes, and Toilet Waters

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/71.4.821 ◽

1988 ◽

Vol 71 (4) ◽

pp. 821-823

Author(s):

Harris H Wisneski ◽

Ronald L Yates ◽

John A Wenninger

Keyword(s):

Emission Intensity ◽

Fluorescence Emission ◽

Water Mixture ◽

Cinnamyl Alcohol ◽

Fluorometric Determination ◽

Short Column ◽

Fluorescence Emission Intensity ◽

Liquid Chromatographic

Abstract A liquid chromatographic (LC) method is described for the determination of cinnamyl alcohol (3-phenyl-2-propen-l-ol) in fragrance compositions. The fragrance product is partially cleaned up by diluting the fragrance with a 95% ethanol-water mixture and passing it through a short column containing RP-8 packing. An aliquot of the effluent is then analyzed by LC using an RP-18 column interfaced to a spectrophotofluorometer equipped with double monochromators. The fluorescence emission intensity of the eluted cinnamyl alcohol is measured and compared with that of a standard to calculate the amount of cinnamyl alcohol present. Recoveries from fragrance products fortified with cinnamyl alcohol at levels ranging from 0.0020 to 0.060 mg/mL ranged from 85 to 105% with a mean of 94%. The lowest level of determination was 0.0005 mg/mL.

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Polycyclic Aromatic Hydrocarbon Solute Probes. Part V: Fluorescence Spectra of Pyrene, Ovalene, Coronene, and Benzo[ghi]perylene Dissolved in Liquid Alkylammonium Thiocyanate Organic Salts

Applied Spectroscopy ◽

10.1366/0003702894203444 ◽

1989 ◽

Vol 43 (7) ◽

pp. 1149-1153 ◽

Cited By ~ 16

Author(s):

Kenneth W. Street ◽

William E. Acree ◽

John C. Fetzer ◽

Prabhakara H. Shetty ◽

Colin F. Poole

Keyword(s):

Polycyclic Aromatic Hydrocarbon ◽

Aromatic Hydrocarbon ◽

Emission Intensity ◽

Fluorescence Spectra ◽

Fluorescence Emission ◽

Fluorescence Properties ◽

Organic Salts ◽

Polycyclic Aromatic ◽

Fluorescence Emission Intensity ◽

Intensity Ratios

Fluorescence properties of pyrene (Py), benzo[ghi]perylene (BPe), coronene (Co), and ovalene (Ov) dissolved in n-butylammonium thiocyanate, sec-butylammonium thiocyanate, and dipropylammonium thiocyanate are reported. Solvent polarities of the thiocyanate salts are estimated from the fluorescence emission intensity ratios of bands I and III (i.e., Py = I/III) of the polycyclic aromatic hydrocarbon vibronic spectra. Calculated BPe, Co, and Ov values indicate that all three thiocyanate salts are comparable in polarity to cyclohexanone.

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Photoisomerization and optical properties of a subphthalocyanine–azobenzene–subphthalocyanine triad

RSC Advances ◽

10.1039/c6ra11452k ◽

2016 ◽

Vol 6 (75) ◽

pp. 71199-71205 ◽

Cited By ~ 3

Author(s):

Maohu Shi ◽

Yue Zhao ◽

Haijun Xu ◽

John Mack ◽

Luan Yin ◽

...

Keyword(s):

Optical Properties ◽

Nmr Spectroscopy ◽

Conformational Change ◽

Emission Intensity ◽

Fluorescence Emission ◽

Azobenzene Moiety ◽

Fluorescence Emission Intensity

A novel subPc–AB–subPc triad exhibits on–off switching of the fluorescence emission intensity upon reversible trans ↔ cis photoisomerization of the azobenzene moiety. NMR spectroscopy provides additional evidence for the conformational change.

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Photo-Induced Fluorescence Enhancement of BOPIM–dma in Moderate Polar Solvents

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.488-489.193 ◽

2014 ◽

Vol 488-489 ◽

pp. 193-196

Author(s):

Jin Dong Gong ◽

Wei Zhang ◽

Ping Shen ◽

Ming Xun Yan ◽

Chang Ying Yang

Keyword(s):

Charge Transfer ◽

Uv Irradiation ◽

Emission Intensity ◽

Fluorescence Enhancement ◽

Polar Solvent ◽

Intramolecular Charge Transfer ◽

Fluorescence Emission ◽

Polar Solvents ◽

Quenching Process ◽

Fluorescence Emission Intensity

The photo-induced fluorescence enhancement for a BOPIM derivate, which was found weak or no fluorescence in solvents due to twisted intramolecular charge transfer (TICT) was investigated. The quenching process because of TICT state is substantially removed and fluorescence emission intensity increased remarkably, induced by UV-irradiation. This phenomenon could only found in moderate polar solvent, such as CHCl3, THF and 1, 4-dioxane (DIOX), but not in more polarity solvent, such as CH3CN, CH3OH. It is indicated that the transformation from TICT to ICT state take place easily in moderate polar solvents.

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