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Journal articles on the topic 'Stern-Volmer quenching'

Author: Grafiati

Published: 4 June 2021

Last updated: 1 February 2022

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1

Moore, Stephanie A., Sarah E. Moore, Karen M. Glenn, Subhash C. Bhattacharya, and Rama M. Palepu. "Fluorescence quenching of Safranine T by inorganic anions in Tween micelles." Canadian Journal of Chemistry 83, no. 12 (2005): 2067–72. http://dx.doi.org/10.1139/v05-225.

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The fluorescence quenching of the dye Safranine T by various inorganic anions such as [Fe(CN6)]3, [Fe(CN6)]4, I, Br, NO2, and N3 in aqueous solution and in nonionic micellar solutions of Tweens (Tween 20, Tween 40, and Tween 80) was studied. The SternVolmer quenching constants and quenching rate constants were evaluated. Compared to the quenching efficiency in aqueous media, that of the micellar media was found to be lower, except when iodide ion was used as a quencher. With the exception of the iodide ion, it has been established that collisional quenching plays a major role in the photophysical process. In the case of the iodide ion, both static and collisional quenching processes play a major role, owing to the complexation of iodide ion with Tween micelles. The SternVolmer quenching constants were found to be dependent on the ionic strength of the medium.Key words: fluorescence, static quenching, Tweens, SternVolmer constant, micellar media.

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2

Sidarai, Ashok H., Vani R. Desai, Shirajahammad M. Hunagund, Mahantesha Basanagouda, and Jagadish S. Kadadevarmath. "Effect of solvent polarity on the fluorescence quenching of TMC molecule by aniline in benzene–acetonitrile mixtures." Canadian Journal of Physics 94, no. 11 (2016): 1125–32. http://dx.doi.org/10.1139/cjp-2016-0213.

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The fluorescence quenching of coumarin derivative, 6-methoxy-4-p-tolyloxymethyl-chromen-2-one by aniline is carried out in different solvent mixtures of benzene and acetonitrile at room temperature. The quenching is found to be appreciable and a positive deviation from linearity is observed in the Stern–Volmer plot in all the solvent mixtures. Various rate constants for fluorescence quenching processes have been estimated using a sphere of action static quenching model and a finite sink approximation model. From the positive deviation of linear Stern–Volmer plots and dependence of rate constants on the polarity of the solvents, it has been inferred that the quenching process is diffusion-limited, and static as well as dynamic quenching processes are responsible for the observed positive deviation in the Stern–Volmer plot. Further, both models have been found to agree well with transient state also in pure acetonitrile and benzene solvents.

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3

Ogunsipe, Abimbola, and Tebello Nyokong. "Effects of central metal on the photophysical and photochemical properties of non-transition metal sulfophthalocyanine." Journal of Porphyrins and Phthalocyanines 09, no. 02 (2005): 121–29. http://dx.doi.org/10.1142/s1088424605000186.

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The photophysical and photochemical properties and quenching (by 1,4-benzoquinone) of metallophthalocyanine sulfonates of aluminium ( AlPcSmix), zinc ( ZnPcSmix), silicon ( SiPcSmix), germanium ( GePcSmix) and tin ( SnPcSmix) are presented. The quantum yield values of fluorescence (ΦF), triplet state (ΦT), singlet oxygen (ΦΔ) and photodegradation (Φd) were determined and the observed trends in their variation among the complexes discussed in terms of aggregation and the heavy atom effect. 1,4-benzoquinone effectively quenched the fluorescence of the complexes. Quenching analyses gave positive deviations from Stern-Volmer behavior, suggesting the existence of static quenching in addition to dynamic quenching. The static and dynamic components of the quenching were separated using a modified Stern-Volmer equation and the “sphere of action quenching model”. The quenching constant was found to be a function of the radius of the central metal ion.

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4

Blatt, E., AWH Mau, WHF Sasse, and WH Sawyer. "Simulated Stern-Volmer Plots for 1-1 Ground-State Complexation." Australian Journal of Chemistry 41, no. 1 (1988): 127. http://dx.doi.org/10.1071/ch9880127.

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Stern-Volmer plots are simulated for the case of static quenching due to 1:1 ground-state complexation of quencher and fluorophore in solution, and compared with previously obtained experimental data. For cases where the association constant KC > 105 dm3 mol-1, upward curvatures of Stern- Volmer plots are expected. When KC is between 103 and 105 dm3 mol-1 linearity is obtained, while for KC < 103 dm3 mol-1 upward curvatures are again predicted. The significance of these results to fluorescence quenching experiments in general is discussed.

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5

Thipperudrappa, J., and S. M. Hanagodimath. "Analysis of Fluorescence Quenching of BPBD by Aniline in Toluene." Mapana - Journal of Sciences 12, no. 1 (2013): 87–98. http://dx.doi.org/10.12723/mjs.24.8.

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Fluorescence quenching of 2-(4'-t-Butylphenyl)-5-(4"-biphenylyl)-1,3,4-oxadiazole (BPBD) by aniline in toluene has been carried out at room temperature by steady state and time resolved fluorescence spectroscopy. The Stern-Volmer plot by steady state method has been found to be non-linear showing a positive deviation, whereas by time-resolved method it is linear. In order to interpret these results we have used the ground state complex and sphere of action static quenching models. Using these models various rate parameters have been determined. Based on these models, with finite sink approximation model, we conclude that positive deviation Stern-Volmer plot is due to the simultaneous presence of dynamic and static quenching processes.

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6

Castillo, John, and Herminsul Cano. "Study of the fluorescence quenching of 1-hydroxypyrene-3,6,8-trisulfonic acid by single-walled carbon nanotubes." Universitas Scientiarum 22, no. 3 (2017): 201. http://dx.doi.org/10.11144/javeriana.sc22-2.sotf.

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This paper presents a study of the fluorescence quenching of 1-hydroxypyrene-3,6,8-trisulfonic acid (HPTS) in the presence of single-walled carbon nanotubes (SWCNT) using a fluorescence method. To investigate the quenching mechanism (dynamic or static) of HPTS, Stern-Volmer plots of single walled carbon nanotubes at different temperatures were used. The positive deviation from linearity in Stern-Volmer plots suggests that single walled carbon nanotubes follow a static quenching mechanism evidenced by the formation of a stable ground state complex. The results presented here help us to clarify the quenching mechanism in the interaction of a pyrene derived dye and carbon nanotubes. This study will open new possibilities in the use of the conjugate formed by SWCNTs and HPTS in the fabrication of a<br />biosensor based on intracellular fluorescent probes.

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7

Yekta, Ahmad, Zahra Masoumi, and Mitchell A. Winnik. "Luminescence measurements of oxygen permeation and oxygen diffusion in thin polymer films." Canadian Journal of Chemistry 73, no. 11 (1995): 2021–29. http://dx.doi.org/10.1139/v95-250.

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A new method is developed for analyzing the diffusion of oxygen in thin polymer films via fluorescence quenching measurements. We begin by reviewing previous methods, all of which involve approximations, for the measurement of permeability and diffusion coefficient by luminescence quenching; their shortcomings are clarified. An exact analytic theory is developed that successfully couples Fick's laws of diffusion to the Stern–Volmer equation of intensity quenching. Various modes of experimentation with polymeric films are considered. The equations we derive make the unexpected prediction that the rate of emission intensity decay when O2 diffuses into a polymer film is much faster than the rate of emission intensity enhancement when O2 diffuses out of the same film, even when the molecular diffusivity remains unchanged. Experiments show that this is indeed the observed behaviour. Keywords: diffusion coefficient, oxygen permeability, polymers, quenching, luminescence quenching, Fick's laws. Stern–Volmer equation.

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8

Janosi, Tibor Zoltan, Jouko Korppi-Tommola, Zsolt Csok, Laszlo Kollar, Pasi Myllyperkio, and Janos Erostyak. "Anthracene Fluorescence Quenching by a Tetrakis (Ketocarboxamide) Cavitand." Journal of Spectroscopy 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/708739.

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Quenching of both fluorescence lifetime and fluorescence intensity of anthracene was investigated in the presence of a newly derived tetrakis (ketocarboxamide) cavitand at various concentrations. Time-correlated single photon counting method was applied for the lifetime measurements. A clear correlation between the fluorescence lifetime of anthracene as a function of cavitand concentration in dimethylformamide solution was observed. The bimolecular collisional quenching constant was derived from the decrease of lifetime. Fluorescence intensity was measured in the emission wavelength region around 400 nm as a result of excitation at 280 nm. Effective quenching was observed in the presence of the cavitand. The obtained Stern-Volmer plot displayed upward curvature. The results did not follow even extended Stern-Volmer behavior, often used to describe deviations from static bimolecular quenching. To explain our results we adopted the Smoluchowski model and obtained a reasonable estimate for the molecular radius of the cavitand in solution.

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9

Patil, Shivaram N., F. M. Sanningannavar, B. S. Navati, D. Nagaraja, N. R. Patil, and R. M. Melavanki. "Quenching mechanism of 5BDTC by aniline using Stern–Volmer plots." Canadian Journal of Physics 93, no. 10 (2015): 1076–81. http://dx.doi.org/10.1139/cjp-2014-0613.

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The quenching mechanism of 5,6-benzo-3-[1-(4,5-dicarbomethoxy-1,2,3-triazoloacetyl)] coumarin (5BDTC) by aniline using Stern–Volmer plots in six different solvents, namely, 1,4 dioxane, dimethyl formamide, dichloromethane, toluene, tetrahydrofuran, and acetonitrile. The Stern–Volmer plots are found to be nonlinear with a positive deviation in all six solvents. To interpret these results we have invoked ground-state complex formation and sphere of action static quenching models. Using these models, various quenching rate parameters have been determined. The magnitudes of these parameters suggest that the sphere of action static quenching model agrees well with the experimental results. Hence, the positive deviation is attributed to the static and dynamic quenching. Further, with the use of the finite sink approximation model, it was possible to check these bimolecular reactions as diffusion-limited and to estimate independently distance parameter R′ and mutual diffusion coefficient D. Finally an effort has been made to correlate the values of R′ and D with the values of the encounter distance R and the mutual coefficient D determined using Edward’s empirical relation and the Stokes–Einstein relation.

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10

Deepa, H. R., H. M. Suresh Kumar, M. Basanagouda, and J. Thipperudrappa. "Influence of silver nanoparticles on absorption and fluorescence properties of laser dyes." Canadian Journal of Physics 92, no. 2 (2014): 163–67. http://dx.doi.org/10.1139/cjp-2013-0133.

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The interaction of silver nanoparticles with four laser dyes, namely, LD-425, LD-489, LD-473, and LD-423, dispersed in methanol has been studied at room temperature by absorption and fluorescence spectroscopy. The silver nanoparticles were synthesized by chemical reduction and estimated size is 11 nm according to Mie theory. The changes in absorption spectrum of these dyes with the addition of silver nanoparticles suggest possible interaction with the silver nanoparticles. The magnitudes of the association constants are estimated using the Benesi–Hildebrand model. Fluorescence quenching has been observed for all the dyes with the addition of silver nanoparticles of different concentrations. The Stern–Volmer plots of fluorescence quenching in the case of LD-425 and LD-489 are found to be linear, suggesting the fluorescence quenching is because of the dynamic quenching process. But in the case of LD-473 and LD-423, the Stern–Volmer plots are nonlinear showing positive deviation and the fluorescence quenching in these dyes is because of static quenching processes. Also, it is found that the fluorescence quenching is not solely due to diffusion.

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11

Desilets, David J., Peter T. Kissinger, and Fred E. Lytle. "Improved method for determination of Stern-Volmer quenching constants." Analytical Chemistry 59, no. 8 (1987): 1244–46. http://dx.doi.org/10.1021/ac00135a040.

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12

Goodpaster, John V., and Victoria L. McGuffin. "Rapid and Accurate Determination of Stern—Volmer Quenching Constants." Applied Spectroscopy 53, no. 8 (1999): 1000–1008. http://dx.doi.org/10.1366/0003702991947676.

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13

Acree, William E. "Comments Concerning "The Effect of Temperature on the Fluorescence Quenching of Perylene by Tetrachloromethane in Mixtures with Cyclohexane and Benzene"." Zeitschrift für Naturforschung A 48, no. 12 (1993): 1265–66. http://dx.doi.org/10.1515/zna-1993-1221.

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Abstract An indirect spectrofluorometric probe method is developed for calculating equilibrium constants for formation of heterogeneous solvent-solvent molecular complexes from measured fluorescence emission intensities in select systems that exhibit parabolic-shaped Stern-Volmer quenching plots.

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14

Cao, Li, Parambath Anilkumar, Xin Wang, et al. "Reverse Stern–Volmer behavior for luminescence quenching in carbon nanoparticles." Canadian Journal of Chemistry 89, no. 2 (2011): 104–9. http://dx.doi.org/10.1139/v10-096.

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Photoluminescence properties of carbon nanoparticles from different treatments in various suspensions were evaluated, and the results were in general agreement with those available in the literature. An interesting observation was that the quenching of luminescence emissions in the aqueous suspended carbon nanoparticles by aliphatic amines deviated from the classical Stern–Volmer behavior in a somewhat unusual fashion, exhibiting reversed quenching (increasing luminescence intensities) at very low quencher concentrations. The implication of the observation to the mechanistic framework that may account for photoluminescence emissions in both functionalized and naked carbon nanoparticles is proposed and discussed.

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15

Yang, Yu, та Edward P. C. Lai. "Optimization of Molecularly Imprinted Polymer Method for Rapid Screening of 17β-Estradiol in Water by Fluorescence Quenching". International Journal of Analytical Chemistry 2011 (2011): 1–8. http://dx.doi.org/10.1155/2011/214747.

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A new method was optimized for rapid screening of 17β-estradiol (E2) in water under 10 min. Molecularly imprinted polymer (MIP) particles (325 ± 25 nm) were added in a water sample at pH 5.5 and 20∘C to form a suspension. Fluorescence emission from E2 nonspecifically bound onto the MIP particles was first quenched by large gold nanoparticles (43 ± 5 nm). The Stern-Volmer plot was linear, with dynamic quenching constants (Ksv) of 2.9 ×104 M-1. Fluorescence emission from E2 specifically bound inside the MIP particles was next quenched by small nitrite anions that easily penetrated the imprinted cavities. The Stern-Volmer plot became nonlinear, withKsv= 2.1 × 102 M-1and static quenching constant (V) below 1.0 M-1. The difference between these two emission intensities varied as the initial E2 concentration in water, generating a Scatchard calibration curve withR2>0.97from 0.1 to 10 ppb.

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16

Htun, Than. "A Negative Deviation from Stern–Volmer Equation in Fluorescence Quenching." Journal of Fluorescence 14, no. 2 (2004): 217–22. http://dx.doi.org/10.1023/b:jofl.0000016294.96775.fd.

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17

Hwang, Yu Lien, and Kuo Chu Hwang. "Nonlinear Stern-Volmer Fluorescence Quenching of Pyrene by C60/70." Fullerene Science and Technology 7, no. 3 (1999): 437–54. http://dx.doi.org/10.1080/10641229909350293.

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18

Hasegawa, Tadashi, Ayumi Matsuhisa, and Michikazu Yoshioka. "Stern-Volmer quenching kinetics for use of a dualistic quencher." Journal of Physical Organic Chemistry 6, no. 3 (1993): 160–62. http://dx.doi.org/10.1002/poc.610060306.

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19

Fedorenko, S. G., and A. I. Burshtein. "Deviations from linear Stern–Volmer law in hopping quenching theory." Journal of Chemical Physics 97, no. 11 (1992): 8223–32. http://dx.doi.org/10.1063/1.463445.

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20

Zhang, Haoran, Bingfu Lei, Hanwu Dong, Yingliang Liu, Mingtao Zheng, and Yong Xiao. "Temperature and Oxygen Sensing Properties of Ru(II) Covalently-Grafted Sol–Gel Derived Ormosil Hybrid Materials." Journal of Nanoscience and Nanotechnology 16, no. 4 (2016): 4023–28. http://dx.doi.org/10.1166/jnn.2016.11887.

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In this article, oxygen and temperature-sensing hybrid materials consisting of [Ru(Phen)3]2+ portions covalently-grafted onto the sol–gel derived ormosil network were prepared by co-condensation of tetraethoxysilane (TEOS) using n-octyltriethoxysilane as the network modifier. For comparison purposes, the hybrid materials in which [Ru(Phen)3]2+ were conventionally physically-incorporated into the matrix were also prepared. The obtained hybrid materials were characterized by Fourier transform infrared (FT-IR), luminescence intensity oxygen quenching Stern-Volmer plots, temperature quenching plots and excited-state lifetime. The near linear Stern-Volmer plots can be attributed to the approximate heterogeneous environment of the luminophore within the ormosil materials. The results reveal that the covalently-grafted sample is more sensitive to O2, and has a higher sensing sensitivity and a higher thermal activation energy compared to the physically-incorporated one, since these Ru(II) molecules are strongly covalently-grafted onto the Si–O network via the CH2–Si bonds and less –OH group.

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21

Thanikaivalan, E., and R. Jothilakshmi. "Quenching of Silver Nanoparticles." Materials Science Forum 781 (March 2014): 135–44. http://dx.doi.org/10.4028/www.scientific.net/msf.781.135.

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Silver nanoparticles of different sizes have been prepared. Absorption spectroscopy reveals the formation of ground state complex. Fluorescence spectroscopy has been used to study the signatures of fluorescence quenching. Properties of N-(2-methylthiophenyl)-2-hydroxy-1-naphthaldimine (NMTHN) on silver nanoparticles has been investigated using optical absorption and fluorescence emission techniques. Quenching of fluorescence of N-(2-methylthiophenyl)-2-hydroxy-1-naphthaldimine has been found to decrease with increase in the size of the silver nanoparticles. The results of the quenching experiments were analyzed through Stern Volmer plot.

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22

Wei, Jun, Dongyan Gu, Shengdan Wang, Jinbo Hu, Xiaowu Dong, and Rong Sheng. "Visible-light-mediated radical arylthiodifluoromethylation of isocyanides with fluorinated 2-pyridyl sulfones." Organic Chemistry Frontiers 5, no. 17 (2018): 2568–72. http://dx.doi.org/10.1039/c8qo00644j.

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2-PySO₂CF₂SAr were developed as powerful arylthiodifluoromethylation reagents, and the Stern–Volmer luminescence studies demonstrated that the mechanism might operate via a photoredox cycle consisting of a reductive quenching with Na₂CO₃.

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23

Chen, Jingrun, Jason D. A. Lin, and Thuc-Quyen Nguyen. "Towards a Unified Macroscopic Description of Exciton Diffusion in Organic Semiconductors." Communications in Computational Physics 20, no. 3 (2016): 754–72. http://dx.doi.org/10.4208/cicp.050615.010216a.

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AbstractWe study the exciton diffusion in organic semiconductors from a macroscopic viewpoint. In a unified way, we conduct the equivalence analysis between Monte-Carlo method and diffusion equation model for photoluminescence quenching and photocurrent spectrum measurements, in both the presence and the absence of Förster energy transfer effect. Connections of these two models to Stern-Volmer method and exciton-exciton annihilation method are also specified for the photoluminescence quenching measurement.

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24

Wiczk, Wiesław M., and Tadeusz Latowski. "Photophysical and Photochemical Studies of Polycyclic Aromatic Hydrocarbons in Solutions Containing Tetrachloromethane II. The Solvent Effect on the Fluorescence Quenching of Aromatic Hydrocarbons by Tetrachloromethane." Zeitschrift für Naturforschung A 42, no. 11 (1987): 1290–95. http://dx.doi.org/10.1515/zna-1987-1111.

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Fluorescence quenching of aromatic hydrocarbons in a large concentration range of the quencher has been studied in a variety of two-component mixtures of tetrachloromethane with other solvents. In aliphatic solvents the process could be described by the Stern-Volmer equation, whereas in the remaining mixtures the fluorescence quenching curves showed a parabolic behaviour which has been explained in terms of specific interactions between the components of the mixtures.

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25

Fayed, Tarek A., Gunter Grampp, and Stephan Landgraf. "Fluorescence quenching of aromatic hydrocarbons by nitroxide radicals: a mechanismatic study." International Journal of Photoenergy 1, no. 3 (1999): 173–76. http://dx.doi.org/10.1155/s1110662x99000306.

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The fluorescence quenching of phenanthrene (Phen), 9-cyanophenanthrene (CPhen), 9-cyanoanthracene (CA), perylene (Per), 9,10-dicyanoanthracene (DCA), and 9,10-diphenylanthracene (DPA) using stable nitroxide radicals as quenchers has been studied by steady state and flash photolysis measurements. Both linearity and deviation from linearity in the Stern-Volmer plots have been observed. The active sphere model was used to discuss the upward curvature of the Stern-Volmer plots in case of Per, DCA, and DPA. The bimolecular quenching rate constant(kq)of Phen, CPhen and CA was found to be diffusion controlled while in other cases it is lower than the diffusion limit. On the basis of flash photolysis measurements as well as the overlap between the emission spectra of hydrocarbons and the absorption spectra of radicals, a resonance energy transfer mechanism is taken place in case of Per, DPA, DCA, and CA. For Phen and CPhen where the energy gap between the first excited singlet and the nearest lower triplet state is small, an induced intersystem crossing was suggested. Finally, the quenching process was discussed in terms of the free energy dependence(ΔG)of the electron transfer from nitroxide radicals to the excited hydrocarbons.

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26

Christov, Christo, Dimitar Ianev, Alexandra Shosheva та Boris Atanasov. "pH-Dependent Quenching of the Fluorescence of Tryptophan Residues in Class A β-Lactamase from E. coli (TEM-1)". Zeitschrift für Naturforschung C 59, № 11-12 (2004): 824–27. http://dx.doi.org/10.1515/znc-2004-11-1210.

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We performed an investigation of the pH-dependent quenching of the fluorescence of tryptophan residues of TEM-1 β-lactamase from E. coli by uncharged and charged quenchers. pH-dependent Stern-Volmer constants (KSV/pH) of tryptophan residues allowed us to determine subtle but discrete structurally and functionally important processes.

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27

Siegel, Rachel, and Samantha Glazier. "TNT Sensor: Stern–Volmer Analysis of Luminescence Quenching of Ruthenium Bipyridine." Journal of Chemical Education 98, no. 8 (2021): 2643–48. http://dx.doi.org/10.1021/acs.jchemed.0c01221.

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28

Hamity, M., and R. H. Lema. "The photochemistry of electron donor–acceptor (EDA) complexes in micellar solutions. I. The stilbene–methylviologen system." Canadian Journal of Chemistry 66, no. 7 (1988): 1552–57. http://dx.doi.org/10.1139/v88-252.

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The association constants for the electron donor–acceptor (EDA) complexes formed between both cis-stilbene (cS) and trans-stilbene (tS) as donors and methylviologen (MV+2) as acceptor were determined in ethanol and micellar sodium dodecyl sulfate (SDS) solutions in the range of SDS concentration 0.05–0.1 M. The values obtained in micellar solutions were much higher than those in ethanol and were heavily dependent upon SDS concentration. This effect is due to an increase in the local concentration of the reactants in the micellar pseudophase. The tS fluorescence quenching by MV+2 was also studied in the same solvent media. In ethanol, the Stern–Volmer plot was found to be linear, with quenching constant (KSV) similar to the association constant determined by the absorption method. In micellar solutions, although upward curvature of the Stern–Volmer plots was observed, a reaction scheme based on static quenching via ground state EDA complex is proposed, which explains the experimental results. Irradiation in the absorption band of the EDA complexes formed by tS or cS and MV+2 was carried out in ethanol and SDS solutions, in the absence of oxygen. Only cis–trans isomerization of cS in SDS solution was observed, with a quantum yield value of Φcis = 0.012.

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29

Sidarai, Ashok H., Vani R. Desai, Shirajahammad M. Hunagund, Mahantesha Basanagouda, and Jagadish S. Kadadevarmath. "Fluorescence Quenching of DMB by Aniline in Benzene-Acetonitrile Mixture." International Letters of Chemistry, Physics and Astronomy 65 (April 2016): 32–36. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.65.32.

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The fluorescence quenching of coumarin dye namely 4-(2,6-dibromo-4-methyl-phenoxymethyl)-benzo[h]chromen-2-one [DMB] has been studied by aniline, in a different solvent mixture of benzene (BN) and acetonitrile (AN) at room temperature. The quenching is found to be appreciable and shows positive deviation from linearity in the Stern-Volmer (S-V) plots for all the solvent mixtures. The various rate parameters responsible for fluorescence quenching have been determined using a sphere of action static quenching model and finite sink approximation model. The magnitudes of these rate parameters indicate that positive deviation in the S-V plot is due to both static and dynamic quenching processes.

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30

Dezhampanah, Hamid, Abdol-Khalegh Bordbar, and Yadolahe Khodadusdt. "Spectroscopic Studies on the Interaction of a Water-Soluble Cationic Porphyrin with Bovine Serum Albumin." Analytical Cellular Pathology 36, no. 1-2 (2013): 21–26. http://dx.doi.org/10.1155/2013/439504.

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The interaction of a water-soluble cationic porphyrin, Cobalt(III) 5, 10, 15, 20-tetrakis (1-methylpyridinium-4-yl) porphyrin [Co(III)TMPyP], with bovine serum albumin (BSA) has been studied in 1 mM phosphate buffer pH 7.0 containing 5 mM NaCl by UV-vis absorption, resonance light scattering (RLS) and fluorescence spectroscopies at 25°C. The results of RLS studies represent no aggregate formation of porphyrin in the surface of BSA and low tendency of this porphyrin for aggregate formation.The binding of porphyrin complex to BSA quenches fluorescence emission of BSA via a dynamic mechanism and the quenching process obeys a linear Stern-Volmer relationship. The values of Stern-Volmer constants, KSV, was determined nearly 105M−1, that depend on BSA concentration. The average aggregation number of BSA calculated from the analysis of fluorescence quenching data indicates that absence of any porphyrin induced aggregation of BSA due to its interaction with porphyrin complex. The binding of Co(III) TMPyP had no obvious effect on the molecular conformation of the protein. Electrostatic force played an important role in the binding due to the opposite charges on porphyrin and the protein.

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31

Sung, Jaeyoung, Kook Joe Shin, and Sangyoub Lee. "Theory of diffusion-influenced fluorescence quenching. Effects of static quenching on the Stern-Volmer curve." Chemical Physics 167, no. 1-2 (1992): 17–36. http://dx.doi.org/10.1016/0301-0104(92)80020-v.

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32

Sung, Jaeyoung, Kook Joe Shin, and Sangyoub Lee. "Theory of diffusion-influenced fluorescence quenching. Effect of static quenching on the stern-volmer curve." Chemical Physics 185, no. 3 (1994): 413. http://dx.doi.org/10.1016/0301-0104(94)85005-4.

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33

Launikonis, A., PA Lay, AWH Mau, AM Sargeson, and WHF Sasse. "Light-Induced Electron-Transfer Reactions Involving the Tris(2,2'-Bipyridine)Ruthenium Dication and Related Complexes. 3. Improved Synthesis of 2,2'-Bipyridine-4,4'-Dicarboxylic Acid and Photoreduction of Water by Bis(2,2'-Bipyridine)(2,2'-Bipyridine-4,4'-Dicarboxylic Acid)Ruthenium(II)." Australian Journal of Chemistry 39, no. 7 (1986): 1053. http://dx.doi.org/10.1071/ch9861053.

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The oxidation of 4,4′-dimethyl-2,2′-bipyridine with potassium permanganate in water gives 2,2′-bipyridine-4,4′-dicarboxylic acid and 4′-methyl-2,2?-bipyridine-4-carboxylic acid. The latter acid is oxidized to the diacid by boiling nitric acid. Complexes of the type Ru ( bpy )2L2+ have been prepared where L is 2,2′-bipyridine-4,4′- dicarboxylic acid, diethyl 2,2′-bipyridine-4,4′-dicarboxylate, 4′- methyl-2,2′-bipyridine-4-carboxylic acid and ethyl 4′-methyl-2,2′- bipyridine-4-carboxylate. These complexes have been compared with [ Ru ( bpy )3]2+ as sensitizers for the photoreduction of water. Stern- Volmer analysis has been applied to the quenching of their luminescence by methylviologen (mv2+), [Co(sep)]3+ (sep is 1,3,6,8,10,13,16,19- octaazabicyclo [6.6.6] icosane ) and [Co( CLsar )]3+ ( CLsar is 1-chloro- 3,6,10,13,16,19-hexaazabicyclo[6.6.6] icosane ). Changes in the Stern-Volmer constants have been related to the free energy changes associated with the oxidative quenching and the overall charges of the ruthenium complexes. The rates of formation of hydrogen compared favourably in sacrificial cycles with the ruthenium complexes as sensitizers, mv2+, Co(sep)3+ as electron-transfer agents, platinum/poly(vinyl alcohol) as catalyst, and ethylenediaminetetraacetic acid as electron donor. The results obtained have been discussed in terms of variations in the efficiencies of cage escape in the oxidative quenching and competition between electron transfer and energy transfer.

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34

Chu, Feng Hong, Lei Ye, Jian Qiang Zhang, et al. "Study of TNT Sensor Based on Fluorescence Quenching of Conjugated Polymer MEH-PPV." Applied Mechanics and Materials 58-60 (June 2011): 2688–92. http://dx.doi.org/10.4028/www.scientific.net/amm.58-60.2688.

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A nitro aromatic explosives sensor based on fluorescence quenching was studied in this paper. U-shaped plastic optical fiber was used as sensor head and light emitting conjugated polymer MEH-PPV as fluorescence indictor. The light source was modulated sinusoidal to eliminate the external light disturbance. TNT quenching characteristics of fluorescence intensity were measured; When TNT concentration was lower than 10mg/ml, the relationship between fluorescence intensity and TNT concentration was linearly, when TNT concentration was higher than 10mg/100ml the obtained characteristics showed deviation from linear relation described by Stern-Volmer equation.

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35

Payne, Sarah J., J. N. Demas, and B. A. DeGraff. "Abnormal Behavior in Stern—Volmer Luminescence Quenching Measurements via Apparent Lifetime Methods." Applied Spectroscopy 63, no. 4 (2009): 437–41. http://dx.doi.org/10.1366/000370209787944307.

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J, Thipperudrappa. "Study of Role of Silver Nanoparticles on Spectroscopic Properties of a KetocyanineDye." Mapana - Journal of Sciences 15, no. 1 (2016): 1–16. http://dx.doi.org/10.12723/mjs.36.1.

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The role of silver nanoparticles on spectroscopic properties of the ketocyaninedye 2,5-di[(E)-1-(4- dimethylaminophenyl) methylidine]-1-cyclopentanone (2,5-DMAPMC) has been investigated using absorption and fluorescence spectroscopy. Silver nanoparticles are synthesized by chemical reduction method and estimated size from SEM measurements is 22 nm. The changes in absorption spectrum of dye in the presence of silver nanoparticles suggest the possible interaction with silver nanoparticles. The Stern-Volmer plot of fluorescence quenching is found to be nonlinear showing positive deviation. The magnitude of quenching rate parameter and fluorescence lifetime measurements indicates the presence of both collisional and static quenching mechanisms. The binding constant and number of binding sites for static part of the quenching have been

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37

Ding, Mei, Ying Jie Lei, Fang Xu, and Ou Yang Jie. "Study on the Interaction of Fluorescent Probe 2-(2'-Chloro Phenyl)-5-(2'-Hydroxyl Phenyl)1,3,4-Oxadiazole with DNA." Advanced Materials Research 284-286 (July 2011): 2392–96. http://dx.doi.org/10.4028/www.scientific.net/amr.284-286.2392.

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The interaction between self-synthesized fluorescent probe 2-(2'- Chloro phenyl)- 5- (2'- hydroxyl phenyl)1,3,4-oxadiazole (HOXD) and Calf thymus DNA was studied using UV absorption spectra and fluorescence quenching spectra．The data of fluorescence quenching of HOXD by DNA were analyzed according to Stern-Volmer equation and Lineweaver-Burk double-reciprocal equation．The results indicated that the fluorescence quenching of HOXD might be static one attributed to the formation of adduct from HOXD and DNA, which was confirmed by the data of temperature effect experiment. Further results presented in the paper showed that intercalation binding might be the interaction mode between HOXD and DNA.

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38

Vasseur, M., R. Frangne, and F. Alvarado. "Buffer-dependent pH sensitivity of the fluorescent chloride-indicator dye SPQ." American Journal of Physiology-Cell Physiology 264, no. 1 (1993): C27—C31. http://dx.doi.org/10.1152/ajpcell.1993.264.1.c27.

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The fluorescence intensity of 6-methoxy-N-(3-sulfopropyl)quinolinium (SPQ) in an N-2-hydroxyethylpiperazine-N'-2-ethanesulfonic acid (HEPES) 2-(N-morpholino)ethanesulfonic acid (MES)-Tris(hydroxymethyl)aminomethane buffer, pH 7.0, decreased as a function of Cl- concentration and/or gluconate concentration, as expected. Contrary to expectation, however, the fluorescence intensity progressively increased as the pH decreased, independently of the presence of gluconate. Consequently, the modulation of SPQ fluorescence by commonly used buffers was investigated as a function of pH. Titration curves demonstrated SPQ quenching and yielded pK values characteristic of each buffer. from here, pH-independent Stern-Volmer constants, KQbase, were calculated for each of the morpholine derivatives, MES and 3-(N-morpholino)-2-hydroxypropanesulfonic acid. In contrast, HEPES and piperazine-N,N'-bis(2-ethanesulfonic acid), which are piperazine derivatives, exhibited an additional pH-independent "molecular" quenching constant KmQ throughout the pH range 3-10. To study chloride fluxes, therefore, what counts is the apparent Cl-Stern-Volmer constant KappCl, which is a function of both pH and buffer composition. Equations describing these relationships are presented. In conclusion, unless both pH and the buffer composition are taken into account, SPQ is unsuitable for studying the concomitant transmembrane fluxes of Cl- and H+.

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39

Naumann, Wolfgang. "Reversible fluorescence quenching: Generalized Stern–Volmer equations on the basis of self-consistent quenching constant relations." Journal of Chemical Physics 112, no. 16 (2000): 7152–57. http://dx.doi.org/10.1063/1.481325.

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40

Shin, Bomina, and Honglae Sohn. "Heavy Atom Effect on Metallole Nanoaggregates and Their Explosive Sensing Applications." Journal of Nanoscience and Nanotechnology 20, no. 9 (2020): 5599–603. http://dx.doi.org/10.1166/jnn.2020.17638.

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Electronic and optical properties of metallole nanoaggregates (M = Ge and Sn) were investigated. Amplified photoluminescence (PL) properties, absolute quantum yields (QY), and critical aggregation concentrations for the metallole nanoaggregates were measured. The an aggregation-induced emission enhancement (AIEE) property decreases as the central atom becomes heavier in the metallole ring. Detection of TNT was achieved by the quenching PL of the metallole nanoaggregates. A linear Stern–Volmer relationship was observed for the detection of TNT.

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41

Martins, Cátia D. F., M. Manuela M. Raposo, and Susana P. G. Costa. "Intermolecular Quenching of Edans/Dabcyl Donor–Acceptor FRET Pair." Proceedings 41, no. 1 (2019): 34. http://dx.doi.org/10.3390/ecsoc-23-06613.

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The intermolecular quenching between 5-(2′-aminoethyl)aminonaphthalene sulfonic acid (Edans) and 4-[[4′-(N,N-dimethylamino)phenyl]diazenyl]benzoic acid (Dabcyl) was studied by photometric and fluorimetric measurements at pH 7.5 in phosphate buffer. The spectral properties of the Edans/Dabcyl donor–acceptor pair were determined and Dabcyl exhibited an intense absorption band at 463 nm, contributing to the quenching efficiency. We also found the primary requirement for fluorescence resonance energy transfer (FRET), the excellent overlap between the fluorescence emission spectrum of the donor molecule and the absorption spectrum of the acceptor molecule, resulting in efficient energy transfer. The quenching mechanism was studied using the Stern–Volmer plot, confirming that this FRET pair was involved in a dynamic quenching process.

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42

Wang, Qing Ming, Jia Liu, Tian Xing Zhang, Feng Zhu, and Xin Hui Tang. "The Investigation of the Interaction between Daidzin and Bovine Serum Albumin by Fluorescence Spectroscopy." Applied Mechanics and Materials 664 (October 2014): 402–9. http://dx.doi.org/10.4028/www.scientific.net/amm.664.402.

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We investigated the mutual interaction of daidzin with bovine serum albumin (BSA) by fluorescence spectroscopy. The results revealed that daidzin cause the fluorescence quenching of BSA through a static quenching procedure. The Stern-Volmer quenching constant (Ksv) were calculated at different temperature. The binding site (n), apparent binding constant (Ka) and corresponding thermodynamic parameters △Go, △Ho, △Sowere calculated and the van der Waals interaction, hydrogen bonds and hydrophobic interactions play an important role in stabilizing the complex. Besides, we also studied the effect of Cu2+, Ni2+, Mn2+and Co2+on the binding constants between daidzin and BSA, it is shows that the binding of BSA and daidzin is strengthened in the presence metal ions.

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43

Will, A. Yvette, Arsenio Muñoz De La Peña, Thilivhali T. Ndou та Isiah M. Warner. "Influence of Triethanolamine on Aqueous β-Cyclodextrin/Pyrene Complexes". Applied Spectroscopy 49, № 4 (1995): 520–25. http://dx.doi.org/10.1366/0003702953964192.

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The influence of triethanolamine (TEA) on the aqueous β-CD/pyrene fluorescence is examined. Collisional quenching of pyrene by TEA is indicated by Stern-Volmer plots. However, a decrease in the quenching is observed in the presence of β-cyclodextrin, which indicates an effective protection of the included pyrene molecules against quenching from TEA. A decrease in the apparent formation constant of the β-CD/pyrene complex also occurs in the presence of TEA. This phenomenon is attributed to a combination of an increased bulk solvent hydrophobicity and a competitive equilibrium between pyrene and TEA for the β-CD cavity. The present study indicates that TEA is not co-included in the β-CD/pyrene complex.

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44

Grigoryan, K. R., H. A. Shilajyan, and V. A. Hovhannisyan. "BOVINE SERUM ALBUMIN FLUORESCENCE QUENCHING BY TANNIC ACID IN DIMETHYLSULFOXIDE CONTAINING SOLUTIONS." Proceedings of the YSU B: Chemical and Biological Sciences 54, no. 2 (252) (2020): 99–104. http://dx.doi.org/10.46991/pysu:b/2020.54.2.099.

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Bovine serum albumin (BSA) interaction with tannic acid (TA) has been studied in dimethylsulfoxide (DMSO) aqueous solutions at different temperatures (293 and 303 K). To find out the fluorescence quenching mechanism of BSA in the presence of TA, the fluorescence data were analyzed according to the modified Stern-Volmer equation based on the approach of the existence of a “sphere of action” (a type of apparent static quenching). The values of apparent static and bimolecular quenching constants were calculated. The effect of DMSO and temperature on BSA–TA interactions is explained on the basis of structural changes in the “sphere of action” of the fluorophore due to the possible inclusion of DMSO molecules in this sphere.

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45

Canuel, Clelia, Sophie Badre, Henning Groenzin, Markus Berheide, and Oliver C. Mullins. "Diffusional Fluorescence Quenching of Aromatic Hydrocarbons." Applied Spectroscopy 57, no. 5 (2003): 538–44. http://dx.doi.org/10.1366/000370203321666560.

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The quenching of the fluorescence of five aromatic hydrocarbons by three halogenated organics and by molecular oxygen has been measured. Both fluorescence intensity and fluorescence lifetime measurements have been employed to validate results and interpretation; linear Stern–Volmer analyses are shown to apply throughout. The fluorescence quenching rate constant of molecular oxygen for the five aromatic hydrocarbons is essentially equivalent to the diffusion rate constant independent of the fluorophore excitation energy. The halogenated organic–fluorophore rate constants vary by a factor of 965 and are shown to correlate roughly with the energy difference between the quencher and fluorophore excited electronic states in accord with a standard model of quantum two-level mixing. The value of the coupling interaction energy is ∼2500 cm−1.

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46

Deepa, H. R., J. Thipperudrappa, and H. M. Suresh Kumar. "A study on fluorescence quenching of a laser dye by aromatic amines in alcohols." Canadian Journal of Physics 93, no. 4 (2015): 469–74. http://dx.doi.org/10.1139/cjp-2014-0190.

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The fluorescence quenching of 1,2,3,8-tetrahydro-1,2,3,3,8-pentamethyl-5-(trifluoromethyl)-7H-pyrrolo[3,2-g]quinolin-7-one (LD-473) by aromatic amines, namely, aniline, dimethyl aniline, and diethyl aniline, in methanol, ethanol, propanol, and butanol has been studied at room temperature using steady-state and time-resolved methods. A positive deviation from linearity has been observed in Stern–Volmer (S–V) plots. Various quenching rate parameters have been determined using the extended S–V equation and are found to be dependent on the dielectric constant of alcohols. The quenching ability of amines increases with increasing their ionization energies. Further, with the use of the sphere of action, static quenching model, and finite sink approximation model, it is concluded that the bimolecular quenching reactions are due to the combined effect of both dynamic and static quenching processes.

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47

Tasic, Uros S., Ernest R. Davidson, and Charles S. Parmenter. "Non-Stern−Volmer Quenching of S1pDFB Fluorescence by O2and the Charge Transfer Complex†." Journal of Physical Chemistry A 107, no. 18 (2003): 3552–58. http://dx.doi.org/10.1021/jp022281y.

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Igoshin, O. A., and A. I. Burshtein. "Impurity quenching of fluorescence in intense light. Violation of the Stern–Volmer law." Journal of Chemical Physics 112, no. 24 (2000): 10930–40. http://dx.doi.org/10.1063/1.481732.

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49

Zeng, Hualing, and Gilles Durocher. "Analysis of fluorescence quenching in some antioxidants from non-linear Stern—Volmer plots." Journal of Luminescence 63, no. 1-2 (1995): 75–84. http://dx.doi.org/10.1016/0022-2313(94)00045-e.

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50

Melavanki, R. M., R. A. Kusanur, J. S. Kadadevaramath, and M. V. Kulakarni. "Quenching mechanisms of 5BAMC by aniline in different solvents using Stern–Volmer plots." Journal of Luminescence 129, no. 11 (2009): 1298–303. http://dx.doi.org/10.1016/j.jlumin.2009.06.011.

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