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Tseng LH, Braumann U, Godejohann M, Lee SS, Albert K. Structure Identification of Aporphine Alkaloids by On-Line Coupling of HPLC-NMR with Loop Storage. J CHIN CHEM SOC-TAIP 2013. [DOI: 10.1002/jccs.200000168] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Duarte IF, Legido-Quigley C, Parker DA, Swann JR, Spraul M, Braumann U, Gil AM, Holmes E, Nicholson JK, Murphy GM, Vilca-Melendez H, Heaton N, Lindon JC. Identification of metabolites in human hepatic bile using 800 MHz 1H NMR spectroscopy , HPLC-NMR/MS and UPLC-MS. ACTA ACUST UNITED AC 2009; 5:180-90. [DOI: 10.1039/b814426e] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Cloarec O, Campbell A, Tseng LH, Braumann U, Spraul M, Scarfe G, Weaver R, Nicholson JK. Virtual Chromatographic Resolution Enhancement in Cryoflow LC−NMR Experiments via Statistical Total Correlation Spectroscopy. Anal Chem 2007; 79:3304-11. [PMID: 17394288 DOI: 10.1021/ac061928y] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
A new approach to enhancing information recovery from cryogenic probe "on-flow" LC-NMR spectroscopic analyses of complex biological mixtures is demonstrated using a variation on the statistical total correlation spectroscopy (STOCSY) method. Cryoflow probe technology enables sensitive and efficient NMR detection of metabolites on-flow, and the rapid spectral scanning allows multiple spectra to be collected over chromatographic peaks containing several species with similar, but nonidentical, retention times. This enables 1H NMR signal connectivities between close-eluting metabolites to be identified resulting in a "virtual" chromatographic resolution enhancement visualized directly in the NMR spectral projection. We demonstrate the applicability of the approach for structure assignment of drug and endogenous metabolites in urine. This approach is of wide general applicability to any complex mixture analysis problem involving chromatographic peak overlap and with particular application in metabolomics and metabonomics.
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Affiliation(s)
- Olivier Cloarec
- Department of Biomolecular Medicine, Division of Surgery, Oncology, Reproductive Biology and Anaesthetics, Faculty of Medicine, Imperial College London, South Kensington, London SW7 2AZ, UK
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Hiller W, Pasch H, Macko T, Hofmann M, Ganz J, Spraul M, Braumann U, Streck R, Mason J, Van Damme F. On-line coupling of high temperature GPC and 1H NMR for the analysis of polymers. J Magn Reson 2006; 183:290-302. [PMID: 17045499 DOI: 10.1016/j.jmr.2006.09.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2006] [Revised: 08/17/2006] [Accepted: 09/07/2006] [Indexed: 05/12/2023]
Abstract
The on-line coupling of gel permeation chromatography (GPC) and 1H NMR operating at temperatures up to 130 degrees C is presented. A NMR flow probe with a cell volume of 120 microL and a stop-flow valve are developed for on-flow and stop-flow NMR measurements at high temperatures. To maintain high and constant temperatures through the whole probe, the flow probe contains two separate heating circuits. A modified stop-flow valve is developed as a control device for enabling on-flow and stop-flow experiments at high temperature conditions. Heated transfer lines connect the flow probe with the high temperature GPC system. Due to their semicrystalline nature, polyolefins can be studied by liquid chromatography only at temperatures above 100 degrees C. The novel high temperature GPC-NMR system is used for the separation of complex polyolefins regarding their molar mass and for the analysis of different chemical structures. Blends of polyethylene, poly(methyl methacrylate), and ethylene-methyl methacrylate copolymers are separated according to the molar masses of the components. The compositions of the components are directly studied by on-line NMR. Moreover, the chemical composition distribution of an ethylene-methyl methacrylate copolymer sample is analysed. Differences between results of on-flow and stop-flow measurements are discussed.
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Affiliation(s)
- Wolf Hiller
- German Institute for Polymers (DKI), Schlossgartenstr. 6, 64289 Darmstadt, Germany.
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Schefer AB, Braumann U, Tseng LH, Spraul M, Soares MG, Fernandes JB, da Silva MFGF, Vieira PC, Ferreira AG. Application of high-performance liquid chromatography–nuclear magnetic resonance coupling to the identification of limonoids from mahogany tree (Switenia macrophylla, Meliaceae) by stopped-flow 1D and 2D NMR spectroscopy. J Chromatogr A 2006; 1128:152-63. [PMID: 16904679 DOI: 10.1016/j.chroma.2006.06.059] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2005] [Revised: 06/09/2006] [Accepted: 06/19/2006] [Indexed: 11/17/2022]
Abstract
Separation and characterization of limonoids from Switenia macrophylla (Meliaceae) by HPLC-NMR technique has been described. Analyses were carried out using reversed-phase gradient HPLC elution coupled to NMR (600 MHz) spectrometer in stopped-flow mode. Separated peaks were collected into an interface unit prior to NMR measurements, which were performed with suppression of solvent signals by shaped pulses sequences. Structure elucidation of the limonoids was attained by data obtained from 1H NMR, TOCSY, gHSQC and gHMBC spectra without conventional isolation that is usually applied in natural products studies.
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Affiliation(s)
- Alexandre B Schefer
- NMR Division, Bruker BioSpin GmbH, D-76287 Rheinstetten, Silberstreifen, Germany.
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Bieri S, Varesio E, Veuthey JL, Muñoz O, Tseng LH, Braumann U, Spraul M, Christen P. Identification of isomeric tropane alkaloids from Schizanthus grahamii by HPLC-NMR with loop storage and HPLC-UV-MS/SPE-NMR using a cryogenic flow probe. Phytochem Anal 2006; 17:78-86. [PMID: 16634283 DOI: 10.1002/pca.889] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Two fully automated HPLC-NMR methods are reported and compared for the structure elucidation of four isomeric tropane alkaloids from the stem-bark of an endemic Chilean plant, Schizanthus grahamii Gill. (Solanaceae). The first approach interfaced a conventional HPLC column to NMR by means of a loop storage unit. After elution with a mobile phase consisting of deuterated water and standard protonated organic solvents, the separated analytes were momentarily stored in a loop cassette and then transferred one-at-a-time to the NMR flow probe for measurements. The second strategy combined HPLC with parallel ion-trap MS detection and NMR spectroscopy using an integrated solid-phase extraction (SPE) unit for post-column analyte trapping. The SPE cartridges were dried under a gentle stream of nitrogen and analytes were sequentially eluted and directed to a cryogenically cooled flow-probe with an NMR-friendly solvent. The structures of the four isomeric alkaloids, 3alpha-senecioyloxy-7beta-hydroxytropane, 3alpha-hydroxy-7beta-angeloyloxytropane, 3alpha-hydroxy-7beta-tigloyloxytropane and 3alpha-hydroxy-7beta-senecioyloxytropane, were unambiguously determined by combining NMR assignments with MS data.
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Affiliation(s)
- Stefan Bieri
- Laboratory of Pharmaceutical Analytical Chemistry, School of Pharmaceutical Sciences EPGL, University of Geneva, 20 Bd d'Yvoy, 1211 Geneva 4, Switzerland
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Godejohann M, Tseng LH, Braumann U, Fuchser J, Spraul M. Characterization of a paracetamol metabolite using on-line LC-SPE-NMR-MS and a cryogenic NMR probe. J Chromatogr A 2004; 1058:191-6. [PMID: 15595667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/01/2023]
Abstract
In this study, the hyphenation of LC-SPE-NMR-MS at 500 MHz was applied to the structural elucidation of a low concentrated paracetamol metabolite present in human urine. Single or multiple peak trapping of the mass detected metabolite on SPE cartridges was employed to increase the sensitivity and quality NMR measurement over the conventional LC-NMR method. After the elution of the metabolite from the SPE cartridge to the NMR flow probe using deuterated acetonitrile for initial NMR investigation, the fraction was revovered by flushing the sample out of the NMR probe head with nitrogen gas. On the recovered fraction, high resolution FT-ICR-MS measurements were conducted, giving exact mass information about the unknown metabolite. In addition, a cryogenic NMR micro probe head was used to enhance the sensitivity of the NMR measurement by a factor of 5 in order to run 2D experiments for structural elucidation of the unknown metabolite. The combination of both MS and NMR results, led unequivocally to the elucidation of the structure as the ether glucuronide of 3-methoxyparacetamol.
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Simpson AJ, Tseng LH, Simpson MJ, Spraul M, Braumann U, Kingery WL, Kelleher BP, Hayes MHB. The application of LC-NMR and LC-SPE-NMR to compositional studies of natural organic matter. Analyst 2004; 129:1216-22. [PMID: 15565221 DOI: 10.1039/b408064e] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Non-living natural organic matter (NOM) is ubiquitous in the oceans, atmosphere, sediments, and soils, and represents the most abundant organic carbon reserves on earth. However, a large proportion is considered to be "molecularly uncharacterized" because the inherent complexity of NOM is problematic when applying conventional analytical techniques. This manuscript presents initial applications of LC-NMR (1H) and LC-SPE-NMR (1H) to the studies of NOM isolated from water and soil. LC-NMR is applied to dissolved natural organic matter (DNOM) collected from freshwater environments, and both LC-NMR and LC-SPE-NMR are applied to an alkaline soil extract. The polar and complex nature of the DNOM samples limits conventional reversed phase separation, which can be partially overcome with the use of an ion pair reagent, although such an approach further complicates the NMR detection. LC-SPE-NMR of the soil alkaline extract was encouraging, and specific components in the mixture could be assigned. This work demonstrates that it is both possible to separate and concentrate specific components in NOM such that NMR detection is possible. As NMR information will be critical in unraveling the novel and/or complex structures in NOM this represents a key analytical hurdle in this area.
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Affiliation(s)
- Andre J Simpson
- Department of Physical and Environmental Sciences, University of Toronto, Scarborough Campus, Toronto, ON, Canada.
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Duarte IF, Godejohann M, Braumann U, Spraul M, Gil AM. Application of NMR spectroscopy and LC-NMR/MS to the identification of carbohydrates in beer. J Agric Food Chem 2003; 51:4847-4852. [PMID: 12903934 DOI: 10.1021/jf030097j] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The application of LC-NMR/MS for the direct identification of carbohydrates in beer has been studied. Carbohydrates are major beer components, and their structural characterization by NMR alone is seriously hindered by strong spectroscopic overlap. Direct analysis of beer by LC-NMR/MS enables the rapid (1-2 h) identification of dextrins with degree of polymerization (DP) of up to nine monomers, with degassing being the only sample treatment required. Although the presence of alpha(1-->6) branching points is easily indicated by NMR for each subfraction separated by LC, difficulties arise for the unambiguous assignment of linear or branched forms of high DP dextrins. The two beer samples investigated in this work were found to have significantly different oligosaccharide compositions, reflecting the different production conditions employed. The use of hyphenated NMR for the rapid characterization of the carbohydrate composition of beers may be the basis of a useful tool for the quality control of beer.
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Affiliation(s)
- Iola F Duarte
- Department of Chemistry, Campus de Santiago, University of Aveiro, 3810-193 Aveiro, Portugal
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Gil A, Duarte I, Godejohann M, Braumann U, Maraschin M, Spraul M. Characterization of the aromatic composition of some liquid foods by nuclear magnetic resonance spectrometry and liquid chromatography with nuclear magnetic resonance and mass spectrometric detection. Anal Chim Acta 2003. [DOI: 10.1016/s0003-2670(03)00579-8] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Affiliation(s)
- K Albert
- Institut für Organische Chemie, Universität Tübingen, Germany
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Nadelmann L, Tjørnelund J, Hansen SH, Cornett C, Sidelmann UG, Braumann U, Christensen E, Christensen SB. Synthesis, isolation and identification of glucuronides and mercapturic acids of a novel antiparasitic agent, licochalcone A. Xenobiotica 1997; 27:667-80. [PMID: 9253144 DOI: 10.1080/004982597240262] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
1. Four glucuronic acid conjugates of licochalcone A (Lica), and their metabolites, have been synthesized using rabbit and pig liver microsomes and purified by preparative hplc. 2. The glucuronides were identified as E-Lica 4'-O-beta-glucuronide, E and Z-Lica 4-O-beta-glucuronide and a mono-glucuronide conjugate of a beta-hydroxylated Lica metabolite. The metabolites were identified by hplc-nmr (one and two-dimensional nmr) as well as hplc-ms. 3. At pH 8.5 Lica reacted with N-acetyl-L-cysteine giving the two epimeric conjugates, which were then isolated by preparative hplc and identified by one and two-dimensional nmr spectroscopic methods. 4. Only two glucuronic acid conjugates (E- and Z-Lica 4-O-beta-glucuronide) were found in the urine of rat after i.p. administration of a single dose of Lica.
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Affiliation(s)
- L Nadelmann
- Department of Analytical and Pharmaceutical Chemistry, Royal Danish School of Pharmacy, Copenhagen, Denmark
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Schlotterbeck G, Tseng LH, Händel H, Braumann U, Albert K. Direct On-Line Coupling of Capillary HPLC with 1H NMR Spectroscopy for the Structural Determination of Retinyl Acetate Dimers: 2D NMR Spectroscopy in the Nanoliter Scale. Anal Chem 1997; 69:1421-5. [DOI: 10.1021/ac960902b] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Götz Schlotterbeck
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany, and Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany
| | - Li-Hong Tseng
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany, and Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany
| | - Heidrun Händel
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany, and Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany
| | - Ulrich Braumann
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany, and Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany
| | - Klaus Albert
- Institut für Organische Chemie, Universität Tübingen, Auf der Morgenstelle 18, D-72076 Tübingen, Germany, and Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany
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Spraul M, Braumann U, Renault JH, Thépenier P, Nuzillard JM. Nuclear magnetic resonance monitoring of centrifugal partition chromatography in pH-zone-refining mode. J Chromatogr A 1997. [DOI: 10.1016/s0021-9673(96)01038-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Sidelmann UG, Braumann U, Hofmann M, Spraul M, Lindon JC, Nicholson JK, Hansen SH. Directly Coupled 800 MHz HPLC−NMR Spectroscopy of Urine and Its Application to the Identification of the Major Phase II Metabolites of Tolfenamic Acid. Anal Chem 1997. [DOI: 10.1021/ac960582w] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ulla Grove Sidelmann
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - Ulrich Braumann
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - Martin Hofmann
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - Manfred Spraul
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - John C. Lindon
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - Jeremy K. Nicholson
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
| | - Steen Honoré Hansen
- Department of Analytical and Pharmaceutical Chemistry, The Royal Danish School of Pharmacy, Universitetsparken 2, DK-2100 Copenhagen, Denmark, Bruker Analytische Messtechnik GmbH, Silberstreifen, D-76287 Rheinstetten, Germany, and Department of Chemistry, Birkbeck College, University of London, Gordon House, 29 Gordon Square, London WC1H 0PP, U.K
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Scarfe GB, Wilson ID, Spraul M, Hofmann M, Braumann U, Lindon JC, Nicholson JK. Application of Directly Coupled High-performance Liquid Chromatography–Nuclear Magnetic Resonance–Mass Spectrometry to the Detection and Characterisation of the Metabolites of 2-Bromo-4-trifluoromethylaniline in Rat Urine. ACTA ACUST UNITED AC 1997. [DOI: 10.1039/a608050b] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Albert K, Schlotterbeck G, Tseng LH, Braumann U. Application of on-line capillary high-performance liquid chromatography-nuclear magnetic resonance spectrometry coupling for the analysis of vitamin A derivatives. J Chromatogr A 1996. [DOI: 10.1016/0021-9673(96)00454-2] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Albert K, Schlotterbeck G, Braumann U, Händel H, Spraul M, Krack G. Structure Determination of Vitamin A Acetate Isomers through Coupled HPLC and1H NMR Spectroscopy. ACTA ACUST UNITED AC 1995. [DOI: 10.1002/anie.199510141] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Albert K, Schlotterbeck G, Braumann U, Händel H, Spraul M, Krack G. Strukturbestimmung von Vitamin-A-acetat-Isomeren mit HPLC-1H-NMR-Kopplung. Angew Chem Int Ed Engl 1995. [DOI: 10.1002/ange.19951070919] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Albert K, Braumann U, Streck R, Spraul M, Ecker R. Application of direct on-line coupling of HPLC and SFC with 1HNMR spectroscopy for the investigation of monomeric acrylates. ACTA ACUST UNITED AC 1995. [DOI: 10.1007/bf00323378] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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