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Summary

A new liquid chromatography tandem mass spectrometry (LC-MS/MS) assay for the quantification of seven isoflavones (daidzin, genistin, ononin, daidzein, glycitein, genistein, and formononetin) and coumestrol in vegetable extracts was developed. The separation was performed on a Zorbax SB-C18 column with a mixture of methanol (solvent A) and 0.1% (υ/υ) acetic acid in water (solvent B) under gradient conditions at 50°C with a flow rate of 1 mL min−1. The detection of analytes was performed by electrospray ionization, negative ionisation, in non-reactive MS2 mode for aglycons or in reactive MS2 mode for glycosides. The method shows a good linearity (r 2 > 0.9948) over the concentration range of 40–4000 ng mL−1 for all analytes, a good precision (CV < 11%) and accuracy (<10%). The method was successfully applied to quantify the isoflavones and coumestrol in vegetable extracts obtained from red clover (Trifolium pratense L., Fabaceae) and dyer's greenweed (Genista tinctoria L., Fabaceae) and can be used in the chemical characterization of vegetables with phytoestrogen content.

Open access

drug detection and prone to cross-reaction between metabolites of the drugs [ 6 , 7 ], and several antiepileptics, e.g. valproic acid and gabapentin, exhibit no UV absorption [ 8 ]. In recent years, liquid chromatography tandem mass spectrometry (LC-MS/MS

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.N. Chen 2009 Protein profile in hepatitis B virus replicating rat primary hepatocytes and HepG2 cells by iTRAQ-coupled 2-D LC-MS/MS analysis: Insights on liver angiogenesis Proteomics

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]. However, GLYP and GLUF were frequently not detected after derivatization, especially after acylated derivatized sample analyses. Recently, Yoshioka et al. reported an analytical method using liquid chromatography (LC)–MS/MS for bialaphos (BIA

Open access
Acta Chromatographica
Authors:
Jong-Woo Jeong
,
Yun-Hwan Seol
,
Hun-Chan Hyun
,
Hye-Rim Kim
,
Jong-Hwa Lee
,
Young-Dae Gong
,
Nam Sook Kang
, and
Tae-Sung Koo

chromatography–tandem mass spectrometry (LC–MS/MS). This method was successfully used in the pharmacokinetic studies of supinoxin in rats and may be useful for the development of clinical data. Experimental Reagents and

Open access

chromatography–tandem mass spectrometry (LC–MS/MS) in human plasma [ 3 – 6 ]. Moreover, there are reports available on synthesis and characterization of process-related impurities of olmesartan medoxomil [ 7 , 8 ]. AT is also reported for the determination of

Open access

a freeze dryer (Virtis advantage 2 XL) to yield impurity-1 and impurity-5. LC-MS/MS conditions LC-MS/MS analysis was carried out on Applied biosystems triple quadruple mass spectrometer (AB SCEIX QTRAP 4500) coupled with a Shimadzu UHPLC with LC-30

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fungicide, such as difenoconazole, propiconazole, mandipropamid, or cyflufenamid, has been extensively studied [ 4 , 9–14 ], and their residues have been determined mainly by HPLC-UV [ 13 ], GC-ECD [ 9 ], GC-FID [ 14 ], GC-MS [ 14–17 ] and LC-MS/MS [ 12

Open access

approach coupled with LC–MS/MS for analysis of polyoxin B in cucumber and soil was developed. Meanwhile, negative ion mode (ESI − ) and positive ion mode (ESI + ) were compared with mass spectrometry. This method was successfully used to research the role

Open access

-cutting 2D-LC coupled to tandem mass spectrometer (2D-LC‒MS/MS) method and optimization of sample preparation procedures for the quantification of mometasone furoate in human plasma and apply it to a BE study in Chinese health volunteers who received

Open access