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1

Screening of active components as scavenger of radical from perennial fujimoto bean (Hyacinth Bean) whole herb by HPLC-MS coupled radical reaction

Shi G. F., Wang Z. J., Wang G.Y., Yao R. X., Chen F. W., Shi Z. R.

Acta Chromatographica

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2016

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Vol. 28, no. 1

19--31

EN

High-performance liquid chromatography-mass spectrometry (HPLC-MS) method coupled with radical reaction for screening active ingredients from perennial fujimoto bean whole herb was established. The active ingredients, present in perennial fujimoto bean whole herb, possess scavenging effects towards 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical, superoxide, peroxy radical, and hydroxyl radical. The radical scavenging abilities of these active ingredients were evaluated based on the relative peak areas in the HPLC chromatogram. The results indicate that potent antioxidants are present in the anhydrous methanol extract of perennial fujimoto bean whole herb. Based on HPLC-MS analysis, it was found that the scavenging ability can be mostly attributed to the presence of three compounds: cyanidin-3-o-β-d-glucopyranoside, troxerutin, and rutin. The structures were identified based on the MS and nuclear magnetic resonance (NMR) data. Free radical scavenging activity decreased in the following order: troxerutin > rutin > cyanidin-3-o-β-d-glucopyranoside.

2

Simultaneous determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines by ultra-performance LC-ESCI-MS/MS multiple reaction monitoring

Wang G. Y., Shi Y. P.

Acta Chromatographica

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2014

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Vol. 26, no. 2

229--242

EN

A new method using ultra-performance liquid chromatography (UPLC) in combination with tandem mass spectrometry and a multiple reaction monitoring mode (UPLC-MS/MS-MRM) was developed for simultaneous quantitative determination of anthraquinone derivatives in Radix et Rhizoma Rhei-based medicines. A multi-mode electrospray/chemical ionization (ESCI) and negative ion mode with [M-H]− and its fragments under collision-activated conditions were employed in MS/MS-MRM. The quantitative method was validated and applied to simultaneous determination of anthraquinone derivatives in 21 Radix et Rhizoma Rhei-based medicines. The limits of quantification were in the range of 3.90–9.09 ng mL -1. Average recoveries were between 95.5% and 99.8% with relative standard deviations from 1.8% to 5.3%.

3

Attribute Reduction Using Extension of Covering Approximation Space

Wang G.Y., Hu J.

Fundamenta Informaticae

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2012

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Vol. 115, nr 2/3

219-232

EN

The concept of the complement of a covering is introduced, and then the extended space of a covering approximation space is induced based on it. Generally, the extended space of a covering approximation space generates a bigger covering lower approximation or smaller covering upper approximation than itself. Through extending each covering of a covering decision system, the classification ability of each covering may be improved. Thus, a heuristic reduction algorithm is developed to eliminate some coverings in a covering decision system without decreasing the classification ability of the system for decision. Theoretical analysis and experimental results indicate that this algorithm can often get smaller reduction than other algorithms.

4

Rapid analysis of multiple components in radix et Rhizoma Rhei using ultraperformance liquid chromatography tandem mass spectrometry

Wang G.Y., Xu L. W, Shi Y. P.

Acta Chromatographica

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2011

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Vol. 23, no. 4

653--672

EN

A simple and rapid method, using online ultraperformance liquid chromatography with photodiode array detection and electrospray ionization mass spectrometry (UPLC-PDA-eλ-ESI-MS/MS), was developed for the in-depth analysis of 50 batches Radix et Rhizoma Rhei. The analysis was performed on a UPLC BEH C18 column using a gradient elution system. Baseline separation could be achieved in less than 7.5 min. At the same time, on the basis of the 50 batches of samples collected from representative cultivated regions, a novel chromatographic fingerprint was devised by UPLC-PDA, in which 27 common peaks were detected and identified by the developed UPLC-MS/MS method step by step according to fragmentation mechanisms, MS/MS data, standards, and relevant literature. Many active components gave prominent [M - H]− ions in the ESI mass spectra. These components include anthraquinones, sennosides, stilbenes, glucose gallates, naphthalenes, and catechins. Furthermore, based on the information of these Radix et Rhizoma Rhei components, and further combined with discriminant analysis, a novel discriminant analysis equation (DAE) was established for the quality control of Radix et Rhizoma Rhei for the first time.

5

Hollow-fiber liquid-phase microextraction combined with high-performance liquid chromatography for analysis of melamine in milk products

Wang G.Y., Chen J., Shi Y. P.

Acta Chromatographica

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2010

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Vol. 22, no. 2

307--321

EN

A novel liquid-phase microextraction (LPME) technique, based on a hollow fiber (HF), in conjunction with high-performance liquid chromatography, has been developed for analysis of melamine in milk products. Melamine was extracted directly from milk products by use of a hollow-fiber membrane filled with organic solvent. HFLPME conditions, for example pH, extraction solvent, temperature, stirring rate, and extraction time were optimized. The best extraction efficiency of melamine was achieved under the conditions: pH 9.5, 35 μL n -octanol as extraction solvent, temperature 55°C, stirring rate 300 rpm, and extraction time 30 min. The HF-LPME technique resulted in a preconcentration ratio of 29-fold. Baseline chromatographic separation of melamine was achieved on a C 18 column with 96:4 ( v / v ) 0.02 mol L -1 ammonium sulfate-methanol as isocratic mobile phase. The linearity of the method ranged from 1.0 to 100.0 μg mL -1, correlation coefficient 0.9994. The limit of detection by use of HF-LPME was 0.021 μg mL -1 at a signal-to-noise ratio of 3. The optimized HF-LPME technique was successfully applied to the analysis of melamine in milk products collected from different commodity manufacturing units.

6

Method development and validation for simultaneous HPLC analysis of six active components of the Chinese medicine Qin-Bao-Hong antitussive tablet

Chen J., Wang G.Y., Shi Y. P.

Acta Chromatographica

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2009

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Vol. 21, no. 2

341--354

EN

A high-performance liquid chromatographic (HPLC) method coupled with photodiode array (PDA) detection has been developed and validated for simultaneous analysis of six active components (syringin, hyperoside, baicalin, quercetin, baicalein, and farrerol) of the Chinese medicinal preparation Qin-Bao-Hong antitussive tablet. The optimum conditions for separation were achieved on a 3.9 mm × 150 mm i.d., 5-μm particle, C 18 column with a linear mobile phase gradient prepared from acetonitrile and 1% acetic acid at a flow rate of 1.0 mL min -1 . Because of the different UV characteristics of these compounds, four detection wavelengths were used for the quantitative analysis (265 nm for syringin, 256 nm for hyperoside and quercetin, 277 nm for baicalin and baicalein, and 296 nm for farrerol). For all the analytes a good linear regression relationship ( r > 0.999) was obtained between peak area and concentration over a relatively wide range. The method was validated for repeatability, precision, stability, accuracy, selectivity, and robustness. The validated method was successfully applied to simultaneous analysis of these active components in Qin-Bao-Hong antitussive tablet from different production batches.