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1. |
Use of a New Diaminobutane Dendrimer in Electrokinetic Capillary Chromatography |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 611-624
JudsonL. Haynes,
ShahabA. Shamsi,
Joykrishna Dey,
IsiahM. Warner,
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摘要:
A modified polyamidoamine-starburst dendrimer (PAMAM-SBD), 16-cascade:(1,4-diaminobutane)[4-1,4]:(1,6-diaza-7-oxo-nonyl idene)2:propanoic acid methyl ester (DABD), was synthesized and used as a carrier in electrokinetic capillary chromatography. The utility of DABD is demonstrated with the separation of a mixture of naphthalene derivatives and five neutral aromatic molecules without the need for an organic solvent as a modifier. Separation of a mixture of five neutral aromatic molecules were optimized through dendrimer concentration, pH, and organic modifier. The modified polyamidoamine-starburst dendrimer offered selectivity for polynuclear aromatic hydrocarbons as well as naphthalene based derivatives. However, DABD did not provide as much selectivity for neutral aromatic compounds in the presence of organic modifier.
ISSN:1082-6076
DOI:10.1080/10826079808005845
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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2. |
The Statistical Evaluation of Migration Parameters of Flavonoids in Capillary Electrophoresis with Reference to Structural Descriptors |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 625-643
Hai-Rui Liang,
Heikki Vuorela,
Pia Vuorela,
Raimo Hiltunen,
Marja-Liisa Riekkola,
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摘要:
Under each of 38 buffer conditions, six migration parameters of 14 flavonoids were obtained in capillary zone electrophoresis (CZE) and nine parameters in micellar electrokinetic capillary chromatography (MEKC). A total of 183 structural descriptors for each flavonoid were calculated to represent the molecular structures in a quantitative way. The relationship between the structural descriptors and the migration parameters of flavonoids in CZE or MEKC were evaluated by cluster and factor analyses.
ISSN:1082-6076
DOI:10.1080/10826079808005846
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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3. |
The Chromatographic Behavior of Coated Stationary Phases with Different Silicas |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 645-655
TaniaA. Anazawa,
IsabelC. S. F. Jardim,
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摘要:
ABSTRACT
ISSN:1082-6076
DOI:10.1080/10826079808005847
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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4. |
Determination of the Composition of Commingled Crude Oil Streams by HPLC-SEC with UV and IR Detection |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 657-667
N. Varotsis,
N. Pasadakis,
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摘要:
An analytical method utilizing the HPLC-SEC fingerprints of crude oils derived from UV-DAD and IR detectors is presented. It can determine rapidly and accurately the contribution of different crude oils in pipeline mixtures and in commingled production streams.
ISSN:1082-6076
DOI:10.1080/10826079808005848
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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5. |
Trace Analysis of Very Long Chain Free Fatty Acids in Plasma by Fluorogenic Derivatization and Liquid Chromatography† |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 669-679
Chin-Fu Chang,
Hsin-Lung Wu,
Shou-Mei Wu,
Su-Hwei Chen,
Hwang-Shang Kou,
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摘要:
A simple and sensitive liquid chromatographic method is described for the simultaneous determination of docosanoic, tetracosanoic and hexacosanoic acids as fluorogenic derivatives. These acids, spiked in plasma, were extracted with n-heptane and the resulting extract was derivatized with 4-bromomethyl-7-methoxycoumarin (BrMmC) in dichloromethane using potassium carbonate and 18-crown-6 as catalysts. The derivatives obtained were chromatographed on a reversed-phase C8column with acetonitrile: water (91: 9, v/v) as a mobile phase and 7-methoxy-4-(tricosanoyloxymethyl)-coumarin as an internal standard. The linear ranges for the determination of docosanoic, tetracosanoic, and hexacosanoic acids were over 31-500, 36-580 and 36-580 pmol, respectively. The limit of detection for each acid was about 0.3 pmol per 10 μL injection (S/N=3).
ISSN:1082-6076
DOI:10.1080/10826079808005849
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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6. |
Utility of Ion-Pair Chromatography for Analysis of Some Anthracyclines in Plasma and Urine |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 681-692
Samy Emara,
Ikue Morita,
Keiko Tamura,
Saeid Razee,
Tsutomu Masujima,
HorriaA. Mohamed,
SamiaM. El. Gizawy,
NawalA. El. Rabbat,
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摘要:
A high performance liquid chromatographic assay was developed and validated for a simultaneous determination of adriamycin and its metabolites adriamycinol and adriamycinone as well as daunomycin in plasma. Acetonitrile and trichloroacetic acid were employed in removing proteins and extracting the drugs and metabolites into the supernatant for HPLC. Enhancement of chemical stability of the anthracyclines during sampling procedure was investigated using 0.01 M γ-cyclodextrin. The processed samples were chromatographed using an ODS/TM column (150 × 4.6 mm I.D.) eluted with a mobile phase composed of 35% acetonitrile and 65% (0.1M) monobasic phosphate, containing 0.3% heptafluorobutyric acid, pH 3.
ISSN:1082-6076
DOI:10.1080/10826079808005850
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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7. |
Reversed-Phase Chromatographic Behavior of Metal Complexes With 8-Hydroxyquinoline and Its Derivatives |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 693-703
Yukio Nagaosa,
Toshihisa Ishida,
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摘要:
Chromatographic behavior of metal complexes with 8-hydroxyquinoline, 5-chloro-8-hydroxyquinoline, and 5,7-chloro-8-hydroxyquinoline in the reversed-phase system has been studied using a variety of organic modifiers. In the acetone modifier system, the capacity factors (k') of the corresponding vanadium(V), nickel(II), and cobalt(III) complexes increased with increasing number of substituted chlorine atoms in the ligands. With acetonitrile-water as the mobile phase, the k' values of the metal 8-hydroxyquinoline complexes decreased with increasing contents of the modifier, depending on the strength of polarity parameters. The k' values, experimentally determined, can be related to the polarity parameters of organic modifiers for tervalent metal ions, but not for monovalent and divalent ions.
ISSN:1082-6076
DOI:10.1080/10826079808005851
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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8. |
Determination of Benzoyl Peroxide in Wheat Flour by Ion Chromatography with Precolumn Derivatization |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 705-716
Qing-Chuan Chen,
Shi-Fen Mou,
Xiao-Ping Hou,
Zhe-Ming Ni,
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摘要:
A novel method for the determination of benzoyl peroxide bleach in wheat flour by using high performance anion exchange chromatography (HPIC) after decomposition to benzoic acid was proposed. Benzoyl peroxide was effectively extracted from wheat flour with absolute ethanol by ultrasonication under neutral condition and converted to benzoic acid in the presence of potassium hydroxide solution. The chromatographic separation of benzoic acid was performed on a Dionex OmniPac PAX-100 separation column and the determination by ultraviolet absorbance detection at 222 nm. Good linearity between the concentration of benzoyl peroxide and peak area response was achieved in the range of 0.12−20 μg/mL. The detection limit (signal-to-noise ratio 3:1) was 19 ng/mL for benzoyl peroxide. The method has been successfully applied for the analysis of real samples, and the average recoveries for various samples ranged from 81 to 92%.
ISSN:1082-6076
DOI:10.1080/10826079808005852
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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9. |
Determination of Arylamine Compounds in Waste Water Using Solid-Phase Extraction and Reversed-Phase High Performance Liquid Chromatography |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 717-724
Shu-Li Zhao,
Fu-Sheng Wei,
Han-Fa Zou,
Xiao-Bai Xu,
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摘要:
A simple, rapid, and sensitive method for determining 10 arylamine compounds in wastewater sample using solid-phase extraction (SPE) and high performance liquid chromatography (HPLC) with UV detection is developed. An SPE procedure is described for extracting and preconcentrating the arylamines on Sep-Pak C18 cartridges with methanol as solvent. A mobile phase gradient of acetonitrile-water was used for the separation and determination of the arylamines.
ISSN:1082-6076
DOI:10.1080/10826079808005853
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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10. |
Enrichment of Nitrophenols in Water by Off- and On-Column Concentration for Capillary Electrophoresis |
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Journal of Liquid Chromatography & Related Technologies,
Volume 21,
Issue 5,
1998,
Page 725-739
Y. He,
H.K. Lee,
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摘要:
A method based on the combined use of off-column solid phase extraction (SPE) using C18membrane disk and on-column field amplified injection (FAI) was developed to isolate, recover, and concentrate nitrophenols in river water prior to analysis by capillary electrophoresis (CE). The effect of eluent, sample pH, and volume in SPE, sample solvent and injection volume in FAI, and the combination of SPE and FAI was investigated in order to find optimal conditions for overall enrichment. With the use of SPE combined with FAI, extraction time was reduced, most interferences were removed, limit of detection was decreased to 5−10 ppb, and recovery of each nitrophenol was > 80%. Combination of off-column SPE and on-column FAI provides a rapid and selective approach for quantitatively concentrating nitrophenols in river water at ppb level prior to CE analysis.
ISSN:1082-6076
DOI:10.1080/10826079808005854
出版商:Taylor & Francis Group
年代:1998
数据来源: Taylor
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