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Near-Infrared Hydrophobic Probes as Molecular Light Switch for CMC Determination of Triton X-100 Solution

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Chinese Journal of Chemistry 2004年第11期22卷 1319-1324页

作者：朱昌青郑洪李东辉李顺华许金钩 The Key Laboratory of Analytical Science of MOE Department of Chemistry Xiamen University Xiamen Fujian 361005 China Cancer Research Center of School of Life Science Xiamen University Xiamen Fujian 361005 China

The fluorescence behavior of two near-infrared (NIR) chromophores with linear alkyl chains of different lengths, 2-[4'chloro-7'(3'ethyl-2'benzothiazolinylidene)-3',5'-(1''',3'''-propanediyl)-1',3',5'-heptantriene-1'-yl]-3-ethylbenzo- thiazolium iodide (Probe I) and 2-[4'chloro-7'(3'hexadecyl-2'benzothiazolinylidene)-3',5'-(1''',3'''-propanediyl)- 1',3',5'-heptantriene-1'-yl]-3-ethylbenzothiazolium iodide (Probe II), in aqueous solution containing different con-centrations of surfactants was studied. The fluorescence of the probe with a short chain (probe I) was completely quenched in water and aqueous solution containing a low concentration (below the critical micelle concentration, CMC) of surfactant Triton X-100. However, the fluorescence reappeared and reached maximum rapidly once the concentration of the surfactant approached the CMC. The probe with a long chain (probe II) displayed a similar fluorescence behavior but more dramatically fluorescent recovery in Triton X-100 system, which gave a direct in-dication for the micelle forming process and provided a simple method for the determination of the critical micelle concentration of the surfactant. The CMC values determined by this method were in good agreement with those ob-tained by other techniques. The fluorescence behavior of the two probes in other surfactant systems was also inves-tigated.

关键词： Triton X-100 critical micelle concentration (CMC) near-infrared (NIR) dye fluorimetry

Fluorescence enhancing by alkaline degradation of tetracycline antibiotics and its application

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Science China Chemistry 1997年第4期40卷 434-441页

作者：赵一兵慈云祥常文保 Department of Chemistry The Research Laboratory of SEDC of Analytical Science for Material and Life ChemistryXiamen UniversityXiamen 361005China Department of Chemistry Peking UniversityBeijing 100871China

Tetracycline antibiotics could be degraded after being beated in boiling-water bath in alkaline solution (in KOH medium).The fluorescence excitation and emission wavelengths of the degradation products changed and the fluorescence intensity increased by 5-190 folds as compared with that of antibiotics themselves It was considered that there occurred a nucleophilic ring rupture reaction to form the degradation products with lactome structure The mteraction of the lone pair electrons of oxygen on the degradation products with the conjugated π electrons induced the in crease of the delocalization for the conjugated electron system in the molecule and thus enhanced the fluorescence intensity.

关键词： tetracycline antibiotics alkaline degradation fluorimetry

Fluorescence　Enhancement　of　Samarium－Thenoyl－trifluoroacetone－Cetyltrimethylammonium　Bromide－Triton　X－100　by　Scandium

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Chemical Research in Chinese Universities 1995年第1期11卷 16-21页

作者： ZHU Gui-yun LIU Ping SI Zhi-kun and HU Jing-tian(Department of Chemistry , Shandong University , Jinan , 250100) SHANDONG UNIV DEPT CHEMJINAN 250100PEOPLES R CHINA

fluorescence enhancement phenomenon shown by adding scandium ion to thesamarium-thenoyltrifluoroacetone (TTA)-cetyltrimethylammonium bromide(CTMAB)-Triton X-100(TX-100) system was observed and the effect of the condi-tions on the system was studied in detail. The excitation and emission wavelengthswere 370 nm, 565 nm, 603 nm and 645 nm, respectively. The optimum conditionsforming Sm-Sc-TTA-CTMAB-TX-100 system were that the concentration of Sc￣(3+)was equal to 5.0× 10￣(-5) mol/L, pH was 7. 7. Under these conditions, the fluores-cence intensity can be increased about 10 times higher than that of the system con-taining no Sc￣(3+) , and it was a linear function of the concentration of samariumn therange of 1. 0 × 10￣(-9)-4. 0 × 10￣(-7) mol/L. The detection limit was 6. 0 ×10￣(-10) mol/*** system was used for the spectrofluorimetric determination of samarium withsatisfactory results. The nature of enhanced fluorescence was explained using in-tramolecular and intermolecular energy transfer theory.

关键词： fluorimetry Samarium Scandium Fluorescence enhancement

Spectrofluorimetric Determination of Trace Terbium(III) Using 2,6-Bis-(1'-phenyl-3'-methyl-5'-oxopyrazole-4')pyridinediacyl and N-Cetylpyridium Bromide

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Chinese Chemical Letters 2000年第5期11卷 431-434页

作者： Jin Zhang GAO Qi Liang DENG Wu YANG Jing Guo HOU Bac Wei ZHAO Jing Wan KANG (Department of Chemistry. Northwest Normal University, Lanzhou 730070) Department of Chemistry Northwest Normal University Lanzhou 730070 China

A new spectrofluorimetric method for determination of trace terbium based on its reaction with 2.6-his-(1'-phenyl-3'-methyl-5'- pyridinediacyl (H_2PMBPP) and N- cetylpyridium bromide (CPB). at an apparent pH=5.0 provided by a hexamethylenetetramine (5% w/w)-hydrochloric acid buffer,is propesed. The calibration graph is linear in the ran ge from

关键词： Spectrofluorimetric terbium determination fluorimetry 2,6-his-(1'-phcnyl-3'- methyl-5'-oxopyrazole-4') pyridinediacyl.

Selective Determination of Epinephrine by Using an Improved Modification of the Trihydroxyindole Method

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Chinese Chemical Letters 1998年第3期9卷 287-289页

作者： Jing He YANG Chang Lun TONG Gut Ling ZHANG Xia WU Cun Guo Lin Jing Tian HU(Department of Chemistry, Shandong University, Jinan 250100) Department of Chemistry Shandong University Jinan 250100 China

A simple and selective method for the determination of epinephrine is put forward, which is an improved modification of the trihydroxyindole method. Experiment indicated that in borax buffer (pH=8.7) and with mercaptoethanol as the reducing reagent, dopa and dopamine did not form fluorescence products, so it is possible to determine epinephrine selectively.

关键词： fluorimetry epinephrine

Characterization and application of PBA fiber optic chemical film sensor based on fluorescence multiple quenching

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Science China(Life Sciences) 1997年第4期40卷 414-421页

作者：陈坚李伟阎超袁立懋郭炬亮周新继 Department of Pharmacy Xinjiang Medical College Urumqi 830054 China

The three types of structure of the pyrenebutyric acid of fiber optic chemical film sensor were stud-ied by fluorescence multiple quenching. They are, for different test samples and purposes, respectively general, three-way and combined. A tri-cup method was designed to demonstrate the multiple quenching of response mechanism, and a relationship formula of mathematical approach was established. The response mechanism was shown to include the dynamic quenching , inner-filter effects and/or resonance energy transfer. To show the response characterization in a series of organic and inorganic quenchers, a new concept of apparent quenching coefficient Kq was advanced. This kind of sensor has been used in continuous and in situ monitoring of the dissolution rate of drug tablets, on line and in situ monitoring of some organic therapeutic drugs in biological fluid and Cr( VI ) in industrial waste water. The measured data were examined and compared with HPLC or HPTLCS. Test results show that the sensors and apparatus are sta-ble and reliable, and their responses to analyte are reversible and rapid, reaching the practical application level.

关键词： fluorimetry fiber-optic sensors pyrenebutyric acid dynamic quenching inner filter effects resonance energy transfer.

Spectrofluorimetric Method for the Determination of Triamcinolone Acetonide

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Wuhan University Journal of Natural Sciences 2004年第3期9卷 353-358页

作者： PanZu-ting YuJun-ping CollegeofChemistryandMolecularSciences WuhanUniversityWuhan430072HubeiChina

A simple and highly sensitive method for the determination of triamcinolone acetonide in pharmaceutical formulations is presented. The approach is based on the fluorescence of production of triamcinolone acetonide oxidized by concentrated sulfuric acid. The effect of H2SO4, β-cyclodextrin (β-CD), solvent and cetyltrimethylammonium bromide (CTMAB) were discussed. And two analytical systems were established. One is CTMAB system, the linear range is 0–4.6×10?6 mol/L, and the detection limit is 3.59×10?8 mol/L. The other is β-CD and ethanol system, the linear range is 0–2.3×10?6 mol/L and the detection limit is 1.91×10?8 mol/L. The selectivity of analysis, the analytical figures of optimization, and the accuracy of the method are demonstrated with the determination of triamcinolone acetonide in pharmaceutical preparations. Key words triamcinolone acetonide - fluorimetry - CTMAB - β-cyclodextrin - pharmaceutical analysis CLC number O 657.39 Foundation item: Supported by the National Natural Science Foundation of China (20275028)Biography: Pan Zu-ting (1945-), male, Professor, research direction: analytical chemistry.

关键词： triamcinolone acetonide fluorimetry CTMAB β-cyclodextrin pharmaceutical analysis

A Study on the Fluorescence System of Sc-BPMPHD-CTMAB and Its Analytical Application

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Chemical Research in Chinese Universities 2000年第1期16卷 93-95页

作者： WU Xia GE Hong-mei HUANG Fang WANG Min YANG Jing-he and CAI Shao-song ( Department of Chemistry, Lab. Colloid & Inter face Chem. for Educational Ministry, Shandong University, Jinan 250100, P. R. China The Import and Export Commodity Inspection Bur 山东大学胶体与界面化学开放实验室山东济南 250100 淄博市进出口商品检验局山东淄博 255310

IntroductionThe fluorescence of Sc3+ itself in solution is not observed. After complexed with an organic ligand with a chromophore, Sc3+ makes the ligand, which has no or has weak fluorescence, emit strong fluorescence.

关键词： fluorimetry Scandium BPMPHD

Organic Solvents Enhanced Spectrofluorimetric Method for Determination of Laccase Activity

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Wuhan University Journal of Natural Sciences 1998年第1期3卷 123-125页

作者： Huang Zuyun, Liu Zhihong, Cat Ruxiu, Zeng Yun’e(Department of Chemistry, Wuhan University,Wuhan 430072, China) Department of Chemistry Wuhan University Wuhan China

A novel fluorimetric method for determination of laccase activity in organic solvents is proposed, based on the oxidation ofo-phenylenediamine (1,2-diaminobenzene, OPDA) catalyzed by laccase yielding 2,3-diaminophenazine. The optimal conditions for laccase in organic media areT=55°C, pH=6.5, 1.0×10?2mol/L OPDA, 1.25 mL ethanol, 1.25 mL 1,4-dioxane and 1.25 mL acetone. The linear range of the method proposed in ethanol, 1,4-dioxane and acetone media were 0.44–19.33, 0.11–20.85, 0.38–21.05 U with the detection limit of 0.088, 0.022, 0.076 U, respectively. The proposed method has been applied to the analysis of laccase activity of real samples with more accurate and sensitive than that of the previous method reported.

关键词： Key words Organic solvent laccase activity fluorimetry o phenylenediamine (OPDA)