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TÜBİTAK

Turkish Journal of Chemistry

Journal

Fluorescence quenching

Publication Year

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng Jan 2018

Exploring Inhibition Of Chemiluminescence Mechanisms With Fluorescence Quenching Studies And Interaction Energy Calculations, Zhenbo Liu, Tangmi Yuan, Yongming Liu, Wenzuo Li, Qingzhong Li, Bo Xiao, Jianbo Cheng

Turkish Journal of Chemistry

Carbamates weaken the luminol-H$_{2}$O$_{2}$ chemiluminescence (CL) catalyzed by sodium copper chlorophyll (SCC). The capacity to inhibit the CL of three carbamates is in the order of carbaryl (CBL) \textgreater carbofuran (CBF) \textgreater metolcarb (MTC). Mechanisms of carbamates inhibiting SCC-luminol-H$_{2}$O$_{2}$ CL are investigated using fluorescence quenching and quantum chemistry simulations for the first time in this work. Carbamate-SCC interactions studied using fluorescence spectroscopy show that with the increasing concentration of the SCC, the fluorescence of carbamate is quenched regularly, and the quenching mechanism is a static quenching process. Binding constants ($K_{B})$ of the three carbamates with SCC are CBL (4.39 x …


A Rapid And Sensitive Spectrofluorometric Method For The Determination Of Au(Iii) Based On Fluorescence Quenching Of A 1,3,5-Triphenyl-2-Pyrazoline, Aysel Başoğlu, Ümmühan Ocak, Seda Fandakli, Nuretti̇n Yayli Jan 2018

A Rapid And Sensitive Spectrofluorometric Method For The Determination Of Au(Iii) Based On Fluorescence Quenching Of A 1,3,5-Triphenyl-2-Pyrazoline, Aysel Başoğlu, Ümmühan Ocak, Seda Fandakli, Nuretti̇n Yayli

Turkish Journal of Chemistry

A simple, rapid, sensitive, and low-cost spectrofluorometric method was developed for the determination of Au(III) using 5-(2,3-dimethoxyphenyl)-3-(4-methoxyphenyl)-1-phenyl-4,5-dihydro-1H-pyrazole (L) in ethanol/water. The method is based on the change in the fluorescence intensity at 464 nm after excitation at 355 nm as a result of the reaction between the ligand and Au(III). The fluorescent emission of ligand at 464 nm decreased with the increasing of Au(III) concentration. The ligand concentration, pH effect, response time, and effect of foreign ions were determined. From the results of fluorescence titration experiments, it was found that the ligand (1 $\times $ 10$^{-7}$ M) was selective and …


Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang Jan 2014

Fluorescence Quenching Study Of Moxifloxacin Interaction With Calf Thymus Dna, Yunkai Lv, Pan Li, Miao-Lun Jiao, Bao-Sheng Liu, Chao Yang

Turkish Journal of Chemistry

Moxifloxacin (MOX) is a fourth-generation synthetic fluoroquinolone antibacterial agent with many important therapeutic properties. Fluorescence quenching was used to study the interaction of MOX with calf thymus DNA (ct-DNA) in aqueous solution. The intercalative binding mode and a static quenching mechanism were confirmed by the Stern--Volmer quenching rate constant (K_q) of 3.48 \times 10^{11} M^{-1} s^{-1} at 298 K. The thermodynamic parameters (\Delta H = --118.4 KJ mol^{-1} and \Delta S = --299.4 J mol^{-1} K^{-1}) were calculated at different temperatures, and they indicate that the main forces between MOX and ct-DNA are hydrogen bonding and Van der Waals force. …


Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut Jan 2014

Synthesis, Characterization, And Photophysical And Photochemical Properties Of 3-(4-Phenyloxy)Coumarin Containing Metallo- And Metal-Free Phthalocyanines, Nurullah Kartaloğlu, Ali̇ye Asli Esenpinar, Mustafa Bulut

Turkish Journal of Chemistry

The synthesis of novel zinc, cobalt, indium, and metal-free phthalocyanines carrying four 3-(4-phenyloxy)couma- rins in the periphery/nonperiphery were prepared by cyclotetramerization of 3-[4-(3,4-dicyanophenyloxy)phenyl]coumarin (2)/3-[4-(2,3- dicyanophenyloxy)phenyl]coumarin (3). The novel chromogenic compounds were characterized by elemental analysis, ^1H NMR, mass spectra, F-IR, and UV-vis spectral data. The effects of the coumarin units on the zinc, indium, and metal-free phthalocyanine complexes (2a/3a, 2c/3c, 2d/3d) were also investigated.


High Rates Of Fluorescence Quenching Between Perylene Dodecyldiimide And Certain \Pi-Electron Donors, S. İçli̇, H. İci̇l, İ. Gürol Jan 1997

High Rates Of Fluorescence Quenching Between Perylene Dodecyldiimide And Certain \Pi-Electron Donors, S. İçli̇, H. İci̇l, İ. Gürol

Turkish Journal of Chemistry

Perylene bis-n-dodecyl diimide is found to quench fluorescenc emissions of naphthalene, phenanthrene and dihydrocarbazolocarbazole molecules at rates of 4.4\times10^{11}, 2.8\times10^{12} and 2.5\times10^4 M^{-1} sec^{-1}, in respective order of aromaticity. These unusulally high rates of fluorecence quenchings are attributed to Perrin model static quenching and presence of electron transfer through singlet excited state of perylene diimide. Calculated free energy of electron transfer, \Delta G_{ET}=-120.5 kJ/mol, between perylene diimide and dihydrocarbazolocarbazole is taken as evidence for observation of high fluorescence quenching rate for carbazolocarbazole molecule. Keywords: Fluorescence quenching, Photoenergy transfer, Perylene diimide and Carbazolocarbazole