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Food and Nutrition Sciences 2014年第9期5卷 823-834页

作者： Yi-Hong Chen Yu-Hui Liu Yi-Jhen Wu Chu-Chin Chen Food Industry Research and Development Institute Hsinchu Taiwan

In this study, a high-performance liquid chromatograph and an electrospray ionization (ESI) triple quadrupole mass spectrometry (TQ MS) detector were used to scan Oriental Beauty tea of different grades and prices. Principle component analysis (PCA) of the profiling data was performed for pattern recognition, clearly showing that the proposed MS profiling method was able to classify Oriental Beauty tea into different grades. The component mass ions primarily responsible for the separation were selected with high loading strength in the PCA for subsequent identification with tandem mass (MS/MS). Caffeine, citrate and salicylate were verified, whereas certain other compounds remained ambiguous. Regression analysis considering caffeine, citrate and salicylate showed a linear relationship between the prices of the Oriental Beauty tea with an adjusted R2 of 0.84. If all the selected marker ions (in addition to caffeine, citrate and salicylate) could have been identified and incorporated into regression analysis, a stronger relationship could have been confirmed. These results suggest that metabolomics can facilitate the determination of real markers in the quality control of Oriental Beauty tea, and may lead to the further application of metabolomics in other food quality controls.

关键词： Dongfang Meiren High Performance Liquid chromatography Mass Spectrometry Metabolic Profiling Metabolomics Oriental Beauty Quality Tea

Packed Supercritical Fluid chromatography for the Analyses and Preparative Separations of Palm Oil Minor Components

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American Journal of Analytical Chemistry 2015年第8期6卷 645-650页

作者： Mei Han Ng Yuen May Choo Engineering and Processing Research Division Malaysian Palm Oil Board Kuala Lumpur Malaysia

This paper depicts a brief review on the applications of packed supercritical fluid chromatography (SFC) in palm oil analyses and purifications from early 1990s to date. Packed SFC has been used for the analyses of various palm oil components. The analytical separations have also been scaled up to preparative scale that leads to the recovery of high value components from palm oil. This review encompasses both analytical and preparative SFC in the oil palm processing.

关键词： Palm Phytonutrients Minor Components Supercritical Fluid chromatography (SFC)

Stereoselective High-Performance Liquid chromatography Tandem Mass Spectrometry Method for Determination of R- and S-Acenocoumarol in Human Plasma and Its Application in a Pharmacokinetics Study

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American Journal of Analytical Chemistry 2015年第3期6卷 216-227页

作者： Isam I. Salem Mahmoud Abdullah Naji Najib International Pharmaceutical Research Center (IPRC) Amman Jordan

A stereoselective, sensitive and rapid liquid chromatography-tandem mass spectrometry (LC-MSMS) method for the determination of R-acenocoumarol and S-acenocoumarol in human plasma was developed and validated at IPRC bioanalytical labs. The procedure involved solid phase extraction of both enantiomers and their corresponding internal standard. The chromatographic separation was accomplished employing a chiral column and proper mobile phase. Detection was carried out using Waters Micromass®Quattro Premier mass spectrometer in multiple reaction monitoring (MRM) mode using turbo ion spray with negative ionization. The method was validated over a linear range of 0.40 - 40.00 ng/ml for R-acenocoumarol and 0.20 - 20.00 ng/ml for the S-acenocoumarol. Method validation covered different parameters such as linearity, accuracy, precision and stability. The method was successfully applied for the determination of R and S-acenocoumarol in plasma samples of 28 healthy subjects who participated in a pharmacokinetics study.

关键词： Stereoselective chromatography Mass Spectrometry LC-MSMS Acenocoumarol Pharmacokinetics

An Economical Method for Preparative Purification of Five Alkaloids from Coptis Chinensis Franch by High-Speed Counter-Current chromatography Using Singled Prepared Solvent System by GC

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American Journal of Analytical Chemistry 2011年第4期2卷 411-421页

作者： Lianhong Yin Lina Xu Xiaona Wang Binan Lu Yingnan Li Mingming Hu Yuetao Liu Jinyong Peng College of Pharmacy Dalian Medical University 9 Western Lvshun South Road Dalian 116044 China

Coptis chinensis Franch, a widely used Traditional Chinese Medicine, shows various kinds of bioactivity. The major active components of the herb are considered to be alkaloids. Thus, preparative separation of these alkaloids is critical important for further pharmacology and mechanism studies. In the paper, five alkaloids from C. chinensis were purified by HSCCC using the solvent system composed of chloro-form-metha- nol-water (2:1:1, v/v/v) single prepared. The content of each solvent in solvent system were determined by gas chromatography (GC), then according the ratios of solvents in each phase to prepare the mobile and stationary phase respectively. And a comparative study was carried out between together preparation and single preparation of the solvent system. The purities and recoveries of all the products were over 98.5% and 92%. However, 134 mL chloroform, 336 mL methanol and 452 mL water were saved when the two phase were singled by GC. Our research showed an economical method for separating alkaloids from C. chinensis by HSCCC using the solvent system single prepared by GC.

关键词： Alkaloid Coptis Chinensis Franch High Speed Counter-Current Chromaotgraphy Gas chromatography Solvent System

Review: Adducts and Clusters in chromatography, Mass Spectrometry and Nature

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International Journal of Analytical Mass Spectrometry and chromatography 2016年第2期4卷 27-33页

作者： Ilia Brondz Norwegian Drug Control and Drug Discovery Institute (NDCDDI) AS Ski Norway

The word “clusters” in scientific terminology as aggregated molecules or atoms appeared in chemistry relatively recently. The terms clusters have been used intensively since the discovery of fullerenes. The term cluster is not a new one for other branches of science such as astrophysics-star cluster, globular cluster, galaxy cluster, in biology and medicine-cancer cluster, genetic cluster, or in computing-data cluster. Adducts in chemistry were known significantly earlier. Both clusters and adducts are assemblies of atoms or molecules that are held together by weak van der Waals or London dispersion forces. Clusters are homogeneous and usually consist of one sort of atom or molecule. Clusters can also be a host for other types of atoms or molecules. Adducts usually consist of two different types of molecules, one of which is the host molecule. Both clusters and adducts are well defined by IUPAC. The present short review describes some important phenomena of these intriguing associations, which have interest for chemical extraction, separation, analysis, and for nature in general.

关键词： Clusters Adducts chromatography Mass Spectrometry Icosahedral Structures

The Detection of THCA Using 2-Dimensional Gas chromatography-Tandem Mass Spectrometry in Human Fingernail Clippings: Method Validation and Comparison with Head Hair

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American Journal of Analytical Chemistry 2013年第10期4卷 1-8页

作者： Joseph Jones Mary Jones Charles Plate Douglas Lewis United States Drug Testing Laboratories Inc. Des Plaines USA

Marijuana use as well as abuse is a significant public health and public safety concern in the United States and using hair to identify marijuana users and abusers has been gaining acceptance in a number of venues including workplace, court ordered, and substance abuse treatment monitoring. After the presentation of a fully validated 2-dimensional gas chromatography-tandem mass spectrometry method for the detection of 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THCA), the chief metabolite of the main psychoactive compound in marijuana, Δ9-tetrahydrocannabinol (THC), we evaluated the usefulness of fingernail clippings as an alternative specimen type to hair by the analysis of a set of 60 matched pairs of head hair and fingernail clippings. The limit of detection was 10 fg/mg, the limit of quantitation was 20 fg/mg, and the assay was linear from 20 fg/mg to 500 fg/mg. The intra- and inter-assay imprecision and bias studies at 4 different concentrations (50, 100, 500, and 1000 fg/mg) were acceptable where all % Target observations were within 16% of their expected concentrations and all %CV calculations were less than 13.5%. THCA was detectable in more fingernail specimens (53.3%) than hair specimens (46.7%) and the mean concentrations in nails were on average 4.9 times higher than in hair (1813 fg/mg and 364 fg/mg, respectively). The THCA concentrations in hair and nail were strongly associated (r = 0.974, P < 0.01, n = 60) and the association was significant. The study demonstrated that fingernail clippings are a suitable alternative specimen type to hair to monitor for marijuana use and abuse.

关键词： 11-Nor-9-Carboxy-Δ9-Tetrahydrocannabinol THCA Carboxy-THC Hair Fingernail 2D-GC-MS/MS 2-Dimensional Gas chromatography Tandem Mass Spectrometry

Modified reversed-phase high performance liquid chromatography for the determination of leukotriene B_4 and 5-hydroxyeicosatetraenoic acid in peripheral neutrophils of rabbits

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Journal of Medical Colleges of PLA(China) 1993年第2期8卷 192-196页

作者：张敏尤忠义雷政宏王风君 Burn Research Institute Southwest HospitalThird Military Medical CollegeChongqing 630038

Modification was made on the reversed-phase high performance liquidchromatography（RP-HPLC）with Yue et al’s method as a base.The modified RP-HPLCwas used to detect leukotriene B4（LTB4）and 5-hydroxyeicosatetraenoic acid（5-HETE）.Itwas found that the modified method has the merits of simpler procedures,shortertesting time and more satisfactory efficacy.

关键词： leukotriene B4 5-hydroxyeicosatetraenoic acid chromatography high performance liquid neutrophils animal rabbits

Column chromatography: A Facile and Inexpensive Procedure to Purify the Red Dopant DCJ Applied for OLEDs

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Advances in Materials Physics and Chemistry 2011年第3期1卷 91-93页

作者： Khadijeh Ghanbari Hassan Aghajani Maryam Golbabaee Elham Naemi Khah Seyed Hassan Nabavi Ata Koohian 不详

DCJ, one of the DCM derivatives, has been used as a laser dye and a red emitter or a red dopant for OLED devices in recent decade. 4-(dicyanomethylene)-2-methyl-6-(julolidyl-9-enyl)-4H-pyran (DCJ) containing julolidine group has been synthesized for use as a red fluorescent dye molecule in organic light-emitting di- odes (OLEDs). In this paper, we reported a facile, simple and inexpensive procedure of purification of DCJ without necessity of HPLC analysis. The maximum absorption, emission, quantum efficiency are increasing in DCJ with the electron-donating of julolidine group.

关键词： Purification Column chromatography Absorption Emission Quantum Efficiency

Determination of Paeonol in Detergent by High Performance Liquid chromatography

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China Detergent & Cosmetics 2019年第3期4卷 63-66页

作者： Wang Juan Lei Min Yu Wen Xi’an Kaimi Co. Ltd.

By analyzing the ultraviolet absorption spectrum of paeonol, selecting the comparatively good test wavelength and separating the appropriate relative flow detergent, the paeonol content in the detergent was measured. By measuring the repeatability, precision and recovery rate, a method for the determination of paeonol in detergent by high performance liquid chromatography was finally established and verified. The experimental results show that the standard solution is linearly correlated between 0.1 and 20 μg ? mL and the recovery rate is 99% to 101%.

关键词： detergent paeonol high performance liquid chromatography

Determination of an Organophosphorus Pesticide Chlorpyrifos in Seawater by Solid Phase Extraction-Gas chromatography

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Meteorological and Environmental Research 2016年第6期7卷 51-53,57页

作者： Liu Zhiju Ji Tiemei Tian Hua Jiang Min Xu Jianping Shanghai Hydrological Station Shanghai Marine Environmental Monitoring Center

Solid phase extraction(SPE) and gas chromatography(GC) were combined to establish a method for detecting traces of chlorpyrifos in seawater,and the effects of extraction column type,water sample pH and salinity,and eluant type on the recovery rate of chlorpyrifos were analyzed. The results show that the linear range of the method was 0.02-2.0 μg/ml,and the correlation coefficient was 0.9993; the recovery rate of chlorpyrifos in the seawater samples to which the standard sample of chlorpyrifos averaged 101%-114%; MDL was 0.00851μg/L,and the lower limit of determination for chlorpyrifos was 0.034μg/L; the relative standard deviation ranged from 1.52% to 6.21%(n = 6). The method is simple,sensitive and accurate and has good repeatability. It is suitable for the determination of traces of chlorpyrifos in seawater.

关键词： Solid phase extraction Gas chromatography Chlorpyrifos Seawater China