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1. |
SIMULTANEOUS DETERMINATION OF THE CYANOTOXINS ANATOXIN A, MICROCYSTIN DESMETHYL-3, LR, RR, AND YR IN FISH MUSCLE USING LIQUID CHROMATOGRAPHY-MASS SPECTROMETRY |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 185-196
Víctor Hormazábal,
Øyvin Østensvik,
Bjarne Underdal,
OlavM. Skulberg,
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摘要:
A liquid chromatographic-atmospheric pressure ionization ion spray method for the determination of anatoxin-a, microcystin desmethyl-3, LR, RR, and YR in fish muscle, is described. A salmon muscle sample was extracted with a mixture of methanol-water and acetone. The organic layer was evaporated and cleaned-up using LMS solid phase extraction columns. The method is simple, specific, and requires only small quantities of chemical reagents. The lower limits of quantification were 15, 2, 10, 1, and 10 ng/g for anatoksin-a, microcystin desmethyl-3, LR, RR, and YR, respectively.
ISSN:1082-6076
DOI:10.1081/JLC-100101444
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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2. |
DETECTION OF BIOTIN BASED ON AN EXCHANGE REACTION WITH AVIDIN-HABA COMPLEX USING CAPILLARY ELECTROPHORESIS |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 197-207
Shunitz Tanaka,
Masanobu Mori,
Kokoro Kodama,
Wenzhi Hu,
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摘要:
The detection of biotin at lower concentration in UV-visible region is difficult because of the low adsorption coefficients. In order to improve this problem, a new migration system, using an exchange reaction between biotin injected and avidin- HABA (2[4’-hydroxyazobenzene] benzoic acid) complex added in running buffer, was developed in the capillary electrophoresis (CE). The use of combination of zwitterionic surfactant (Zwittergent 3–14) and C8 pre-coating capillary enabled this migrating system by suppressing adsorption of avidin for a capillary wall effectively. In this migrating system, the reverse peak height of avidin-biotin complex increased with dependence on concentration of biotin injected. Moreover, the separation of biotin and biocytin was achieved as avidin complex at pH 7 of running buffer. The detection of biotin, contained in a vitamin tablet, was selectively detected avoiding other vitamins by using this CE system. This method enabled detection of only substances having strong affinity with avidin.
ISSN:1082-6076
DOI:10.1081/JLC-100101445
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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3. |
SEPARATION AND DETERMINATION OF TRACE Cu(II), Zn(II), AND Pd(II) AS THEIR TETRAPHENYLPORPHINE CHELATES BY REVERSED-PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 209-222
Zhihong Shi,
Hongyi Zhang,
Chengguang Fu,
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摘要:
α,β,γδ-Tetraphenylporphine (TPP) was used as a precolumn chelating reagent for reversed-phase high performance liquid chromatographic (HPLC) separation and determination of trace Cu2+, Zn2+and Pd2+. Chelating reactions of TPP with Cu2+, Zn2+, and Pd2+have been optimized in the presence of anionic surfactant sodium dodecyl sulphate (SDS). TPP and its metal chelates were successfully separated on a Nucleosil C18column (150×4.6 mm I.D., 5 μm) with acetone-acetonitrile (37.5: 62.5, v/v) as mobile phase.
ISSN:1082-6076
DOI:10.1081/JLC-100101446
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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4. |
COMPARISON OF LYSOZYME ADSORPTION TO IMMOBILIZED CIBACRON BLUE 3GA USING VARIOUS MEMBRANE SUPPORTS |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 223-239
Shing-Yi Suen,
Rui-Long Chen,
Yi-Da Tsai,
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摘要:
Lysozyme adsorption to immobilized Cibacron Blue 3GA using different membrane supports, regenerated cellulose membrane discs, and polysulfone hollow fibers, is investigated in this study. The relevant adsorption properties using traditional chromatographic beads were also measured for comparison. The experimental results demonstrated distinct adsorption properties for different solid supports. The membrane discs possessed the best thermal resistance among the three adsorbents assessed, which essentially results from their higher thermal stability. Moreover, the saturation capacity of lysozyme onto membrane discs was found close to the ligand density for gel beads, whereas the hollow fibers were of much greater saturation capacity.
ISSN:1082-6076
DOI:10.1081/JLC-100101447
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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5. |
CONTINUOUS FLOW METHOD FOR MONITORING PROTEIN PRECIPITATION BY AMMONIUM SULFATE |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 241-249
Yoichiro Ito,
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摘要:
I have proposed “Centrifugal Precipitation Chromatography”[1] as a new method for the precipitation of proteins using a linear gradient of ammonium sulfate (AS). However data on the solubility of proteins under these specific conditions are not available. Therefore, the following method is proposed to obtain these data.
ISSN:1082-6076
DOI:10.1081/JLC-100101448
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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6. |
RAPID ISOCRATIC HPLC ANALYSIS OF HYPERICINS |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 251-259
Tara Sirvent,
DonnaM. Gibson,
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摘要:
We describe a new method for the analysis of hypericins from crude extracts ofHypericum perforatum(St. John’s Wort) using HPLC. Hypericin and pseudohypericin and related compounds were separated in 15 minutes using a simple isocratic elution method on a modified phenyl column. This isocratic method permits the quantitative and rapid analysis of hypericins in crude acetone samples.
ISSN:1082-6076
DOI:10.1081/JLC-100101449
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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7. |
DETERMINATION OF THIABENDAZOLE IN FRUITS AND VEGETABLES BY CAPILLARY ELECTROPHORESIS |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 261-272
DonnaT. Eash,
RodneyJ. Bushway,
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摘要:
A capillary electrophoresis method was developed to quantify thiabendazole in various fruits and vegetables. Thiabendazole was extracted by adding 20 mL of methylene chloride to a 5 gram sample followed by homogenization and centrifugation. A 5 mL aliquot of the supernatant was removed and evaporated under nitrogen. The residue was reconstituted in 1 mL of HPLC grade water acidified with phosphoric acid (pH 3). Quantitation was performed using UV photodiode detection at 298 nm. Intra-assay and inter-assay reproducibility studies run at concentrations from 0.88 ppm to 20.88 ppm indicated the procedure was reproducible.
ISSN:1082-6076
DOI:10.1081/JLC-100101450
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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8. |
CALIBRATION IN QUANTITATIVE TLC BASED ON WEIGHTED REGRESSION FUNCTIONS |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 273-280
C. Sârbu,
Simona Cobzac,
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摘要:
Two methods, one on the basis of relative error in yi(in that case wishould be taken as 1/yi2) (YWLS) and another on the basis of 1/xi2as a weighting factor (XWLS), for the calculation of calibration function are reported and compared with conventional ordinary (OLS) and simple weighted least squares method (WLS). By these procedures the calibration functions for the TLC determination of some triazine herbicides are represented more strongly than by the ordinary least squares method mainly in the cases of heteroscedasticity. Instead of the coefficient of correlation, six coefficients of quality are used to characterize the quality of the calibration functions.
ISSN:1082-6076
DOI:10.1081/JLC-100101451
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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9. |
LIQUID CHROMATOGRAPHIC MONITORING OF PHYTOECDYSTEROID PRODUCTION OFSERRATULA WOLFFII |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 281-294
M. Báthori,
A. Gergely,
H. Kalász,
G. Nagy,
Á. Dobos,
I. Máthé,
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摘要:
Seasonal dependence of 20-hydroxyecdysone content ofSerratula wolffiiwas monitored. Thin-layer chromatography was used after a single clean-up using polyamide. High performance liquid chromatography was employed for the analysis, after removal of the high excess of flavonoids and other impurities using a clean-up on both C18 and polyamide.
ISSN:1082-6076
DOI:10.1081/JLC-100101452
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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10. |
VANCOMYCIN AS A CHIRAL SELECTOR IN CENTRIFUGAL PARTITION CHROMATOGRAPHY |
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Journal of Liquid Chromatography & Related Technologies,
Volume 23,
Issue 2,
2000,
Page 295-312
Ph. Duret,
A. Foucault,
R. Margraff,
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摘要:
The use of vancomycin as a chiral selector was introduced by D. W. Armstrong. This macrocyclic antibiotic was used either free in solution for thin-layer chromatography (TLC) and capillary electrophoresis (CE) or covalently bonded to silica gel in the case of high performance liquid chromatography (HPLC). Its possible use in countercurrent chromatography (CCC) or centrifugal partition chromatography (CPC) is also of interest since these techniques have preparative capabilities which make them attractive for multi-gram scale production of enantiomers.
ISSN:1082-6076
DOI:10.1081/JLC-100101453
出版商:Taylor & Francis Group
年代:2000
数据来源: Taylor
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