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Recent methodology in the phytochemical analysis of ginseng

Angelova, N. (author), Kong, H.-W. (author), van de Heijden, R. (author), Yang, S.-Y. (author), Choi, Y.H. (author), Kim, H.K. (author), Wang, M. (author), Hankemeier, T. (author), van der Greef, J. (author), Xu, G. (author), Verpoorte, R. (author), TNO Kwaliteit van Leven (author)

This review summarises the most recent developments in ginseng analysis, in particular the novel approaches in sample pre-treatment and the use of high-performance liquid-chromatography-mass spectrometry. The review also presents novel data on analysing ginseng extracts by nuclear magnetic resonance spectroscopy and high-resolution mass...

article 2008

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Effects of growth conditions and processing on Rehmannia glutinosa using fingerprint strategy

Chang, W.T. (author), Thissen, U. (author), Ehlert, K.A. (author), Koek, M.M. (author), Jellema, R.H. (author), Hankemeier, T. (author), van der Greef, J. (author), Wang, M. (author), TNO Kwaliteit van Leven TNO Voeding (author)

Metabolite profiling in combination with multivariate statistics is a sophisticated method for quality assessment of natural products. For the development of a quality control strategy in Traditional Chinese Medicine (TCM), we have measured the metabolite fingerprints of Rehmannia glutinosa by GC-MS. Plants were grown under different climate and...

article 2006

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Characterization of anti-inflammatory compounds using transcriptions, proteomics, and metabolics in combination with multivariate data analysis

Verhoeckx, K.C.M. (author), Bijlsma, S. (author), Jespersen, S. (author), Ramaker, R. (author), Verheij, E.R. (author), Witkamp, R.F. (author), van der Greef, J. (author), Rodenburg, R.J.T. (author), TNO Voeding Centraal Instituut voor Voedingsonderzoek TNO (author)

The discovery of new anti-inflammatory drugs is often based on an interaction with a specific target, although other pathways often play a primary or secondary role. Anti-inflammatory drugs can be categorized into classes, based on their mechanism of action. In this article we investigate the possibility to characterize novel anti-inflammatory...

article 2004

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Detection of hormonal anabolic compounds in calf urine and unverified growth-promoting preparations: Application of the AR-LUX bioassay for screening and determination of androgenic activity

Blankvoort, B.M.G. (author), Aarts, J.M.M.J.G. (author), Schilt, R. (author), Geerdink, P. (author), Spenkelink, B. (author), Rodenburg, R.J.T. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

Despite a ban by the European Union, the use of anabolic steroids and repartitioning agents in cattle is still occasionally observed. Due to continuing improvements in analytical techniques, very low detection limits for individual compounds have been achieved. In response to these developments, cocktails composed of several steroids have been...

article 2003

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Bioanalysis of the enantiomers of (+/-)-sarin using automated thermal cold-trap injection combined with two-dimensional gas chromatography

Spruit, W.E.T. (author), Trap, H.C. (author), Langenberg, J.P. (author), Benschop, H.P. (author)

article 2001

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Determination of daminozide in apples and apple leaves by liquid chromatography-mass spectrometry

Mol, H.G.J. (author), van Dam, R.C.J. (author), Vreeken, R.J. (author), Steijger, O.M. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

A straightforward and efficient method was developed for the determination of intact daminozide in apples and apple leaves. After extraction with methanol and a clean-up step using a graphitized carbon cartridge, the extract was analysed by ion-trap liquid chromatography-tandem mass spectrometry (LC-MS-MS) using atmospheric pressure chemical...

article 1999

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Quantification of perifosine, an alkylphosphocholine anti-tumour agent, in plasma by pneumatically assisted electrospray tandem mass spectrometry coupled with high-performance liquid chromatography

Knebel, N.G. (author), Grieb, S. (author), Winkler, M. (author), Locher, M. (author), van der Vlis, E. (author), Verheij, E.R. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

An HPLC assay with tandem mass spectrometric detection in the positive-ion Turbo-Ion-Spray((TM)) (TISP) mode for the fast and sensitive determination of perifosine ((I), D-21266) in human plasma was developed, utilising the structural analogue, miltefosine ((II), D-18506), as internal standard. Automated solid-phase extraction of diluted plasma...

article 1999

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Use of biosensors for rapid drug residue analysis without sample deconjugation or clean-up: A possible way forward

Elliott, C.T. (author), Baxter, G.A. (author), Hewitt, S.A. (author), Arts, C.J.M. (author), van Baak, M. (author), Hellenäs, K.-E. (author), Johannson, A. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

The drug salbutamol (SBL) is a β-agonist that may be used illegally as an animal growth promoter. SBL is also a good example of a drug which is excreted in the form of glucuronides and sulfates. Such metabolites cause complexities in analysing for the presence of drug residues. In the majority of cases a process of deconjugation and sample clean...

article 1998

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In vitro liver models are important tools to monitor the abuse of anabolic steroids in cattle

Centraal Instituut voor Voedingsonderzoek TNO TNO Voeding (author), van Puymbroeck, M. (author), Kuilman, M.E.M. (author), Maas, R.F.M. (author), Witkamp, R.F. (author), Leyssens, T. (author), van der Zande, D.J.M. (author), Gelan, J. (author), Raus, J. (author)

Current veterinary residue analysis mainly focuses on the monitoring of residues of the administered parent compound. However, it is possible that larger amounts of metabolites are excreted and that they can have a prolonged excretion period. In order to unravel specific metabolic steps and to identify possible biological markers, two in vitro...

article 1998

document

Capillary gas chromatographic analysis of nerve agents using large volume injections

Degenhardt, C.E.A.M. (author), Kientz, C.E. (author), TNO Prins Maurits Laboratorium (author)

The use of large volume injections has been studied for the verification of intact organophosphorus chemical warfare agents in water samples. As the use of ethyl acetate caused severe detection problems new potential solvents were evaluated. With the developed procedure, the nerve agents sarin, tabun, soman, DFP and VX can be determined in...

article 1996

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Effects of thiourea and ammonium bicarbonate on the formation and stability of bifunctional cisplatin-DNA adducts: Consequences for the accurate quantification of adducts in (cellular) DNA

Fichtinger-Schepman, A.M.J. (author), van Dijk-Knijnenburg, H.C.M. (author), Dijt, F.J. (author), van der Velde-Visser, S.D. (author), Berends, F. (author), Baan, R.A. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

Cisplatin reacts with DNA by forming mainly bifunctional adducts via reactive monofunctional intermediates. When freshly platinated DNA was postincubated with thiourea (10 mM, at 23 or 37°C) for periods of up to 24 h, followed by determination of mono- and diadducts, a rapid initial decrease was seen in the fraction of diadducts, followed by a...

article 1995

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Pharmacokinetics and bioavailability of dapsone in the beagle dog

Hekman, P. (author), van Rens, P. (author), Rietvel, E.C. (author), Coert, A. (author), Instituut voor Landbouwkundig Onderzoek en Biochemische Produkten TNO (author)

Chemicals/CAS: dapsone, 80-08-0

article 1989

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Fluorometric determination of retinol in human tear fluid using high-performance liquid chromatography

Speek, A.J. (author), van Agtmaal, E.J. (author), Saowakontha, S. (author), Schreurs, W.H.P. (author), van Haeringen, N.J. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

A fast and sensitive high-performance liquid chromatographic (HPLC) method for the determination of vitamin A (all-trans retinol) in 50 ??l human tear fluid is described. After deproteinization with ethanol and extraction with n-hexane, retinol is separated from the extract on a straight-phase HPLC column and detected fluorometrically. Vitamin A...

article 1986

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Microdetermination of vitamin A in human plasma using high-performance liquid chromatography with fluorescence detection

Speek, A.J. (author), Wongkham, C. (author), Limratana, N. (author), Saowakontha, S. (author), Schreurs, W.H.P. (author), Instituut CIVO-Toxicologie en voeding TNO (author)

Chemicals/CAS: n,n dimethylacetamide, 127-19-5; retinol, 68-26-8, 82445-97-4; Vitamin A, 11103-57-4

article 1986

document

PAF-acether-induced release of tissue-type plasminogen activator from vessel walls

Emeis, J.J. (author), Kluft, C. (author), Gaubius instituut TNO (author)

Platelet-activating factor (PAF-acether; 1-O-octadecyl-2-acetyl-sn-glyceryl-3-phosphorylcholine) induced the release of plasminogen activator in rat, both in vivo and in perfused hind legs. The released plasminogen activator was shown by immunologic and functional criteria to be tissue-type plasminogen activator (t-PA). Release of t-PA by PAF...

article 1985

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Determination of progesterone by liquid chromatography - mass spectrometry using a moving-belt interface and isotope dilution

Centraal Instituut voor Voedingsonderzoek TNO (author), van der Greef, J. (author), Tas, A.C. (author), Rijk, M.A.H. (author), ten Noever de Brauw, M.C. (author)

Progesterone can be determined rapidly and accurately with the method presented, using isotope dilution LC-MS with a moving-belt interface. Deactivation is very useful in that it minimizes belt memory effects and optimizes belt desorption characteristics. Since the moving-belt properties were found to change during time with respect to the...

article 1985

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Urine profile analysis by field desorption mass spectrometry, a technique for detecting metabolites of xenobiotics. Application to 3,5-dinitro-2-hydroxytoluene

van der Greef, J. (author), Leegwater, D.C. (author)

A technique for the detection of biotransformation products of xenobiotics in crude urine extracts by field desorption mass spectrometric profile analysis is described. The method comprises determination of peak profiles of a series of blank and test samples using low resolution field desorption mass spectrometry, comparison of averaged peak...

article 1983

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High-performance liquid chromatographic determination of urinary free catecholamines with electrochemical detection after prepurification on immobilized boric acid

Speek, A.J. (author), Odink, J. (author), Schrijver, J. (author), Schreurs, W.H.P. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

A reliable high-performance liquid chromatographic method is presented for the determination of the urinary free catecholamines noradrenaline, adrenaline and dopamine. Urine is purified on a column of immobilized boric acid. Catecholamines are separated by ion-pair reversed phase high-performance liquid chromatography and detected...

article 1983

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Determination of the B2 vitamer flavin-adenine dinucleotide in whole blood by high-performance liquid chromatography with fluorometric detection

Speek, A.J. (author), van Schaik, F. (author), Schrijver, J. (author), Schreurs, W.H.P. (author), Centraal Instituut voor Voedingsonderzoek TNO (author)

A reliable high-performance liquid chromatographic (HPLC) method is developed for the analysis of FAD in whole blood of humans. The method is able to separate FAD, FMN and Rb from each other and from interfering compounds. A reliable and sensitive detection of FAD has been obtained by selecting the optimal pH of the mobile phase and optimal...

article 1982

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A reliable semiautomated method for the determination of total thiamine in whole blood by the thiochrome method with high-performance liquid chromatography

Centraal Instituut voor Voedingsonderzoek TNO (author), Schrijver, J. (author), Speek, A.J. (author), Klosse, J.A. (author), van Rijn, H.J.M. (author), Schreurs, W.H.P. (author)

A sensitive and reliable method for the determination of total thiamine (vitamin B1) in whole blood has been developed which is suited for routine analysis. After extraction, and enzymatic hydrolysis of thiamine phosphate esters, thiamine is separated from interfering compounds by a fully automated high-performance liquid chromatographic (HPLC)...

article 1982