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Simultaneous Determination of Seven Alkaloids in Fufang Zhenzhu Tiaozhi Capsule by HPLC Coupled with DAD

Chinese Herbal Medicines 2012年第3期4卷 230-236页

作者： Yuan-yuan CHEN Jiao GUO Hui FAN Li-hua HUANG Key Unit of Modulating Liver to Treat Hyperlipemia SATCM Level 3 Laboratory of Lipid Metabolism SATCMGuangdong TCM Key Laboratory for Metabolic DiseasesInstitute of Chinese Medicinal SciencesGuangdong Pharmaceutical UniversityGuangzhou 510006China Guangzhou University of Chinese Medicine Guangzhou 510006China

Objective To establish a reverse-phase liquid chromatography method for the determination of seven alkaloids(magnoflorine,columbamine,jatrorrhizine,epiberberine,coptisine,palmatine,and berberine)in Fufang Zhenzhu Tiaozhi *** Chromatography was performed on a Dionex Acclaim C_(18)column(250 mm×4.6 mm,5.0μm)at 30℃.The mobile phase was composed of acetonitrile-potassium dihydrogen phosphate solution(0.015 mol/L,40:60,including 1.7 g/L sodium dodecyl sulfate and phosphoric acid used to regulate pH value to 3.0),with a flow rate of 1.0 mL/*** detection wavelength was 270 *** The calibration curves of magnoflorine,columbamine,jatrorrhizine,epiberberine,coptisine,palmatine,and berberine were linear in the range of 1.07-10.65,0.78-7.55,0.75-7.50,1.60-15.95,2.69-26.85,2.31-23.10,and 6.04-60.40 mg/*** average recoveries of magnoflorine,columbamine,jatrorrhizine,epiberberine,coptisine,palmatine,and berberine were 101.0%,101.2%,100.1%,100.0%,100.1%,101.1%,and 99.7%,*** The method could be used for the quantitative determination of the preparation.

关键词： alkaloids diode array detection Fufang Zhenzhu Tiaozhi Capsule HPLC traditional Chinese medicines

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Determination of some carbamate pesticides in watermelon and tomato samples by dispersive liquid-liquid microextraction combined with high performance liquid chromatography

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INTERNATIONAL JOURNAL OF ENVIRONMENTAL ANALYTICAL CHEMISTRY 2012年第5期92卷 571-581页

作者： Liu, Zhimei Liu, Weihua Rao, Huan Feng, Tao Li, Chao Wang, Chun Wang, Zhi Agr Univ Hebei Coll Sci Key Lab Bioinorgan Chem Baoding 071001 Peoples R China Agr Univ Hebei Coll Food Sci & Technol Baoding 071001 Peoples R China

A novel method for the determination of five carbamate pesticides (metolcarb, carbofuran, carbaryl, isoprocard and diethofencard) in watermelon and tomato samples was developed by dispersive liquid-liquid microextraction (DLLME) coupled with high performance liquid chromatography-diode array detection (HPLC-DAD). Some experimental parameters that influence the extraction efficiency were studied and optimised to obtain the best extraction results. Under the optimum conditions for the method, the calibration curve was linear in the concentration range from 10 to 1000 ng g(-1) for all the five carbamate pesticides, with the correlation coefficients (r) varying from 0.9982 to 0.9992. Good enrichment factors were achieved ranging between 80 and 177, depending on the compound. The limits of detection (LODs) (S/N = 3) were ranged from 0.5 to 1.5 ng g(-1). The method has been successfully applied to the analysis of the pesticide residues in watermelon and tomato samples. The recoveries of the method fell in the range between 76.2% to 94.5% with RSDs less than 9.6%, indicating the feasibility of the DLLME method for the determination of the five carbamate pesticides in watermelon and tomato samples.

关键词： carbamate pesticides high performance liquid chromatography diode array detection dispersive liquid-liquid microextraction watermelon tomato

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Capillary liquid chromatography with diode array and mass spectrometry detection for heterocyclic aromatic amine determination in ready-to-eat food treated with electron-beam irradiation

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JOURNAL OF CHROMATOGRAPHY A 2010年第43期1217卷 6778-6784页

作者： Gonzalo-Lumbreras, R. Rosales-Conrado, N. Leon-Gonzalez, M. E. Perez-Arribas, L. V. Polo-Diez, L. M. Univ Complutense Madrid Fac Chem Dept Analyt Chem E-28040 Madrid Spain

In the present paper, we have developed a capillary liquid chromatography with MS detection for the determination at ng g(-1) levels of four heterocyclic aromatic amines (MelQx, norharman, harman and harmine), a group of mutagenic and carcinogenic compounds that can potentially be produced in protein-rich food during processing operations They have been determined in commercial ready-to-eat (RTE) smoked salmon and soft cheese treated with E-beam irradiation On the basis of experimental design studies and operating conditions of MS detector, best chromatographic conditions were obtained using a Luna (R) C-18 capillary column (150 mm x 0.3 mm 1D.) with a mixture of acetonitrile-ammonium formate 5 mM pH 3.6 buffer (13:87, v/v) as mobile phase To improve sensitivity, large injection volumes (20 mu L) and injection solutions of low elution strength were employed Sample preparation procedure included a previous treatment with 1 M NaOH, followed by two solid-phase extraction steps: firstly on diatomaceous earth and then on mixed-mode cartridges Heterocyclic amines were detected neither in irradiated and in non-irradiated samples, indicating that they were not formed by the radiation effect even at doses higher than those indicated in the Food Safety Objective established by regulatory agencies RTE food samples were spiked at concentration levels in the range 10-30 ng g(-1). Recoveries higher than 85% (n = 3 for each spiked level) were obtained, showing the effectiveness of the proposed methodology (C) 2010 Elsevier B.V. All rights reserved

关键词： Heterocyclic aromatic amines Capillary liquid chromatography Mass spectrometry diode array detection Electron-beam irradiation Ready-to-eat food

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Determination of phoxim residues in eggs by using high-performance liquid chromatography diode array detection after treatment of stocked housing facilities for the poultry red mite (Dermanyssus gallinae)

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ANALYTICA CHIMICA ACTA 2007年第1-2期586卷 330-335页

作者： Hamscher, G. Priess, B. Nau, H. Univ Vet Med Hannover Inst Food Toxicol D-30173 Hannover Germany

The poultry red mite Dermanyssus gallinae is the most important ectoparasite of poultry in several European countries. Phoxim is a well-known antiparasitic agent in wide use. Initial studies indicated that this compound could successfully be applied to eliminate D. gallinae in egg-laying birds and in henhouses by treating the cages and the equipment with it. In order to investigate whether phoxim residues are present in eggs from laying hens, we developed a selective and sensitive high-performance liquid chromatography method employing a simple water/acetonitrile gradient system. The amount of phoxim was determined by UV detection at 281 nm, and the presence of the residue was confirmed by diode array detection. The eggs were homogenized for sample pretreatment and extracted with acetonitrile and partitioned with n-hexane. The acetonitrile extract was further purified with silica gel column chromatography. Recovery rates (performed at the 5-120 mu g kg(-1) level) were in the range of 86.0-92.1% with relative standard deviations between 3.1% and 16.3%. Based on a signal to noise ratio of 3, the limit of detection of the assay was approximately 2 mu g kg(-1). The day-to-day variation in the concentration of phoxim in four contaminated eggs (5.7-51.6 mu g kg(-1)) was generally less than 20%. The decision limit (CC alpha) and the detection capability (CC beta) were 62.0 and 68.7 mu g kg(-1), respectively. The applicability of the method was demonstrated in eggs from three clinical trials and from a field study. In these investigations, all animals were kept in conventional battery cages. No sample was found containing more than the maximum residue level of 60 mu g kg(-1) for phoxim in eggs as given in Annex I of Council Regulation (EEC) No. 2377/90. (c) 2006 Elsevier B.V. All rights reserved.

关键词： battery cages Dermanyssus gallinae diode array detection high-performance liquid chromatography laying hens phoxim

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Relationship between selectivity and average resolution in comprehensive two-dimensional separations with spectroscopic detection

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JOURNAL OF CHROMATOGRAPHY A 2011年第34期1218卷 5819-5828页

作者： Davis, Joe M. Rutan, Sarah C. Carr, Peter W. So Illinois Univ Dept Chem & Biochem Carbondale IL 62901 USA Virginia Commonwealth Univ Dept Chem Richmond VA 23284 USA Univ Minnesota Dept Chem Minneapolis MN 55455 USA

The average value of the multivariate selectivity (SEL) of randomly positioned peaks in a multi-component separation is shown to equal the average fraction of peaks that are singlets, as predicted by statistical-overlap theory (SOT). This equality is the basis for proposing a useful metric, specifically the average minimum resolution of nearest-neighbor peaks, for the performance of comprehensive two-dimensional (2D) separations. Furthermore this metric was computed both without ancillary spectroscopic information and with the assistance of such help, specifically multi-wavelength UV-vis spectra, acquired during the separation. Separations are simulated with randomly positioned peaks over wide ranges of total number of peaks, first- and second-dimension peak capacity, dimensionless first-dimension sampling time, and spectral diversity. The specific version of the general multivariate selectivity concept that is used here - identified as SEL - gives the relative precision of quantification when using the PARAFAC (parallel factor analysis) method, a popular curve resolution algorithm. The SEL values of all peaks were calculated, averaged, and compared to the predictions of SOT. In the absence of auxiliary spectral data, the SEL-based average minimum resolution required to separate two peaks in a 2D separation is 0.256, compared to resolution of 0.5 if no chemometric assistance is available. This was found to be valid over a wide range of conditions and is essentially independent of peak crowding. With the assistance of the spectral data, the requisite minimum resolution substantially improves, that is, it decreases, especially when peak crowding is severe. The requisite minimum resolution decreases even further, up to a limit, as the spectral diversity is increased. In contrast, the SEL-based average under-sampling correction factor is virtually independent of the presence of the additional spectral data, and additionally is about the same as calculated with SOT from

关键词： Multivariate selectivity Resolution Peak-broadening factor Comprehensive two-dimensional separation diode array detection Statistical-overlap theory

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Exploiting second-order advantage using PARAFAC2 for fast HPLC-DAD quantification of mixture of aflatoxins in pistachio nuts

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FOOD CHEMISTRY 2011年第2期127卷 827-833页

作者： Vosough, Maryam Salemi, Amir Chem & Chem Engn Res Ctr Iran Tehran Iran Shahid Beheshti Univ Environm Sci Res Inst Dept Environm Pollut Tehran Iran

A new methodology using second-order calibration based on PARAllel FACtor analysis 2 (PARAFAC2) is developed for fast quantification of aflatoxins B-1, B-2, G(1) and G(2) in pistachio samples by liquid chromatography with diode array detection (LC-DAD). Solvent and solid phase extractions were used for sample preparation steps. In this work, a gradient elution programme was optimised to make co-elutions between analytes and also to shorten the analysis time. Prediction was made on synthetic and real validation samples with a mixture calibration design. Special circumstances such as overlapping of analytes, the lack of spectral selectivity and also the lack of trilinearity, have been compensated with "mathematic separation" through PARAFAC2 modelling. The results showed an acceptable performance of PARAFAC2 for resolution and quantification of all analytes in a single array exploiting the second-order advantage. With the proposed method, the chromatographic run time and also the time for data analysis were reduced significantly. (C) 2011 Elsevier Ltd. All rights reserved.

关键词： Fast chromatography diode array detection PARAFAC2 Aflatoxins

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The UHPLC-DAD fingerprinting method for analysis of extracellular metabolites of fungi of the genus Geosmithia (Acomycota: Hypocreales)

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ANALYTICAL AND BIOANALYTICAL CHEMISTRY 2011年第9期400卷 2943-2952页

作者： Tylova, Tereza Kolarik, Miroslav Olsovska, Jana Acad Sci Czech Republic Inst Microbiol CR-14220 Prague 4 Czech Republic Charles Univ Prague Fac Sci Prague 12840 2 Czech Republic Charles Univ Prague Fac Sci Prague 12801 2 Czech Republic Res Inst Brewing & Malting Prague 12044 2 Czech Republic

A new simple ultra-high-performance liquid chromatography method with diode array detection (UHPLC-DAD) was developed for chemical fingerprinting analysis of extracellular metabolites in fermentation broth of Geosmithia spp. The SPE method employing Oasis MCX strong cation-exchange mixed-mode polymeric sorbent was chosen for extraction of the metabolites. The analyses were performed on an Acquity UPLC BEH C18 column (100 x 2.1 mm i.d.;particle size, 1.7 mu m;Waters) using a gradient elution program with an aqueous solution of trifluoroacetic acid and acetonitrile as the mobile phase. The applicability of the method was proved by analysis of 38 strains produced by different species and isolated from different sources (hosts). The results revealed the correlation of obtained UHPLC-DAD fingerprints with taxonomical identity.

关键词： Ultra-high-performance liquid chromatography diode array detection Solid-phase extraction Extracellular secondary metabolites Geosmithia spp. Chromatographic fingerprinting

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Determination of polyacetylenes in carrot roots (Daucus carota L.) by high-performance liquid chromatography coupled with diode array detection

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JOURNAL OF SEPARATION SCIENCE 2007年第4期30卷 483-490页

作者： Christensen, Lars P. Kreutzmann, Stine Danish Inst Agr Sci Dept Food Sci Res Ctr Aarslev DK-5792 Aarslev Denmark

A new high-performance liquid chromatographic method with diode array detection was developed for the separation and simultaneous determination of the carrot polyacetylenes falcarindiol (FaDOH), falcarindiol 3-acetate (FaDOAc) and falcarinol (FaOH) in carrot root extracts, The optimal chromatographic conditions were achieved on a C18 colunin with a linear gradient elution of water and acetonitrile as mobile phases, at the flow rate of 1.0 mL/min. All calibration curves of the three carrot polyacetylenes showed good linear regression (R-2 > 0.998) within the test ranges. The developed method showed good precision for quantification of all polyacetylenes with overall intraday and interday variation of less than 3.3% and with average recovery rates of 99.2, 96.8 and 99.7% for FaDOH, FaDOAc and FaOH, respectively. The LOD (S/N = 3) and LCQ (S/N = 10) were less than 0.19 and 0.42 mu g/ml, respectively, for all analytes. The established method was successfully used to determine the spatial distribution of FaDOH, FaDOAc and FaCH in six carrot genotypes (Bolero, Independent, Line 1, Mello Yello, Purple Haze and Tornado) by analysing peeled carrots and the corresponding peels for these polyacetylenes.

关键词： carrot Daucus carota diode array detection HPLC falcarinol falcarindiol falcarindiol 3-acetate polyacetylenes

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Validation and global uncertainty of a liquid chromatographic with diode array detection method for the screening of azoxystrobin, kresoxim-methyl, trifloxystrobin, famoxadone, pyraclostrobin and fenamidone in grapes and wine

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ANALYTICA CHIMICA ACTA 2006年 573卷 291-297页

作者： Abreu, Susana de Melo Caboni, Pierluigi Cabras, Paolo Garau, Vincenzo Luigi Alves, Arminda Univ Porto Fac Engn LEPAE DEQ P-4200465 Oporto Portugal Univ Cagliari Dipartimento Tossicol I-09124 Cagliari Italy

Azoxystrobin, kresoxim-methyl, trifloxystrobin, pyraclostrobin, famoxadone and fenamidone are permitted Q Inhibitor (Q(0)I) fungicides applied to vine in some European countries for the treatment of downy and powdery mildews. In this work, a method is validated for the analysis of these fungicides in grapes and wine. This screening method consists in a simple one step liquid-liquid extraction followed by liquid chromatography (LC) fitted with a diode array detector (DAD). Limits of detection for grapes and wine were below 0.2 mg kg(-1) or mg l(-1), precision was not above 13%, and recoveries were, on average, 95 +/- 5% for grapes and 104 +/- 6% for wine. Global uncertainties evaluated in the concentration range from 0.25 to 2.50 mg l(-1) were below 20%. A confirmatory method by gas chromatography (GC) with mass spectrometry (MS) detection was used. (c) 2006 Elsevier B.V. All rights reserved.

关键词： fungicide residues grapes wine method validation liquid chromatography diode array detection

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Simultaneous analysis of Vitamins A and E in infant milk-based formulae by normal-phase high-performance liquid chromatography-diode array detection using a short narrow-bore column

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JOURNAL OF CHROMATOGRAPHY A 2006年第1-2期1122卷 138-143页

作者： Chavez-Servin, Jorge L. Castellote, Ana I. Lopez-Sabater, M. Carmen Univ Barcelona Fac Farm Dept Nutr & Bromatol Ctr Referencia Tecnol Aliments E-08028 Barcelona Spain

A rapid, simple and reproducible normal-phase (NP) high-performance liquid chromatography (HPLC)-diode array detection (DAD) method for simultaneous qualitative and quantitative determination of Vitamin A (retinol acetate and retinol palmitate) and Vitamin E (alpha-tocopherol acetate, alpha-, gamma- and delta-tocopherols) in milk-based infant formulae was developed and validated. The preparation sample was based on protein precipitation and vitamin extraction with ethanol, followed by re-extraction with hexane, while the chromatographic method was based on the use of a short narrow-bore column (50 mm x 2.1 mm;3 mu m particle size), which afforded less solvent consumption and higher mass sensitivity. The method showed acceptable values for precision, recovery and sensitivity, and proved very simple for routine analysis work. (c) 2006 Elsevier B.V. All rights reserved.

关键词： Vitamins A and E infant formula powder diode array detection short narrow-bore column

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