FAST DETERMINATION OF THE FUNCTIONAL PEPTIDE SOYMETIDE IN DIFFERENT SOYBEAN DERIVED FOODS BY CAPILLARY-HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011Elena, Domínguez-Vega , Olga, Kotkowska , M. Concepción, García , Antonio L., Crego , Maria Luisa, MarinaThe determination of b…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011

Elena, Domínguez-Vega , Olga, Kotkowska , M. Concepción, García , Antonio L., Crego , Maria Luisa, Marina

The determination of bioactive peptides derived from food sources is gaining special attention in last years, due to their ability to promote health and their potential to reduce the risk of chronic diseases. In this work, a new analytical methodology has been developed enabling for the first time the determination of soymetide, a new immunostimulating peptide derived from soybean, in different soybean derived foodstuffs. Capillary-HPLC was employed for peptide separation after accelerated tryptic digestion of soybean proteins. Two different capillary-HPLC columns were tested and chromatographic separation was optimized in each case. The use of a 300μm fused-core technology C18 column...

Direct Separation and Detection of Biogenic Amines by Ion-Pair Liquid Chromatography with Chemiluminescent Nitrogen Detector

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011Jingshun, Sun , Hong-Xun, Guo , David, Semin , Janet, CheethamAnalysis of biogenic amines is critical to pharmaceutical and food in…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011

Jingshun, Sun , Hong-Xun, Guo , David, Semin , Janet, Cheetham

Analysis of biogenic amines is critical to pharmaceutical and food industry due to their biological importance. For many years, the determination of biogenic amines has relied on High Performance Liquid Chromatography (HPLC) coupling with pre-, on-, or post-column derivatization procedures to enable UV or fluorescent detections. In this study, 14 biogenic amines were separated on a Phenomenex Luna® Phenyl-Hexyl column by an ion-pair liquid chromatography method using perfluorocarboxylic acids as ion-pair reagents and detected by a Chemiluminescent Nitrogen Detector (CLND). This direct separation and detection HPLC method eliminated the time consuming and cumbersome derivatization procedures. Compared with HPLC-UV (post-column derivatization...

Novel highly hydrophilic methacrylate-based monolithic column with mixed-mode of hydrophilic and strong cation-exchange interactions for pressurized capillary electrochromatography

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011Jia, Lin , Shaofeng, Liu , Jian, Lin , Xucong, Lin , Zenghong, XieA novel highly hydrophilic polymethacrylate-based monolithic sta…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011

Jia, Lin , Shaofeng, Liu , Jian, Lin , Xucong, Lin , Zenghong, Xie

A novel highly hydrophilic polymethacrylate-based monolithic stationary phase based on the copolymerization of 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS) and pentaerythritol triacrylate (PETA) was designed for pressurized capillary electrochromatography. A typical hydrophilic interaction chromatography mechanism could be observed when the content of acetonitrile (ACN) in the mobile phase exceeded 25%. Slight swelling or shrinking with mobile phases of different polarity was observed in permeability studies. Good retentions and efficient separations of polar analytes, such as neutral amides and phenols, were well achieved in hydrophilic interaction chromatography mode with only about 50%ACN content in the mobile phase. It was remarkably lower than the content...

Molecularly imprinted polymer with high-fidelity binding sites for the selective extraction of barbiturates from human urine

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011A., Beltran , F., Borrull , P.A.G., Cormack , R.M., MarcéIn this paper we describe the synthesis of a molecularly imprinted polyme…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011

A., Beltran , F., Borrull , P.A.G., Cormack , R.M., Marcé

In this paper we describe the synthesis of a molecularly imprinted polymer (MIP) by precipitation polymerisation, with barbital as the template molecule, and the application of the barbital MIP as a molecularly selective sorbent in the solid-phase extraction (SPE) of barbiturates from human urine samples.The MIP was synthesised by precipitation polymerisation using 2,6-bis-acrylamidopyridine as the functional monomer and DVB-80 as the cross-linking agent. The spherical MIP particles produced were 4.2±0.4μm in diameter; a non-imprinted control polymer (NIP) in bead form was 4.8±0.4μm (mean±standard deviation) in diameter.The particles were packed into a solid-phase extraction cartridge and employed as a novel sorbent...

Fast-Liquid Chromatography Using columns of different internal diameter packed with sub-2μm Silica Particles.

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011Giovanni, D’Orazio , Anna, Rocco , Salvatore, FanaliCapillary columns (50, 75 and 100μm I.D.) were packed with silica C18 sub-2μ…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 23 May 2011

Giovanni, D’Orazio , Anna, Rocco , Salvatore, Fanali

Capillary columns (50, 75 and 100μm I.D.) were packed with silica C18 sub-2μm particles for 50mm and were employed in nano-liquid chromatography (nano-LC) for fast chromatographic separations. Mixtures of nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids were used as models. Separations no longer than 3minutes were obtained with the three capillary columns employing a mobile phase of 35/65 (v/v) and 45/55(v/v) ACN/H2O in 0.1% formic acid (HFo) for steroids and NSAIDs, respectively. Among the capillary columns used, best results, in terms of retention factor and selectivity, were achieved with the 50μm I.D. column. The same sample mixtures were analyzed by micro-liquid...

Ultrasonic nebulization extraction-heating gas flow transfer-headspace single drop microextraction of essential oil from pericarp of Zanthoxylum bungeanum Maxim.

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Shigang, Wei , Huihui, Zhang , Yeqiang, Wang , Lu, Wang , Xueyuan, Li , …The ultrasonic nebulization extraction – heating gas fl…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Shigang, Wei , Huihui, Zhang , Yeqiang, Wang , Lu, Wang , Xueyuan, Li , ...

The ultrasonic nebulization extraction - heating gas flow transfer coupled with headspace single drop microextraction (UNE-HGFT-HS-SDME) was developed for the extraction of essential oil from Zanthoxylum bungeanum Maxim. The gas chromatography-mass spectrometry was applied to the determination of the constituents in the essential oil. The contents of the constituents from essential oil obtained by the proposed method were found to be more similar to those obtained by hydro-distillation (HD) than those obtained by ultrasonic nebulization extraction coupled with headspace single drop microextraction (UNE-HS-SDME). The heating gas flow was firstly used in the analysis of the essential oil to transfer the...

Use of isopycnic plots in designing operations of Supercritical Fluid Chromatography (SFC) I. The critical role of density in determining the characteristics of the mobile phase in SFC

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Abhijit, Tarafder , Georges, GuiochonIn SFC, the key chromatographic parameters of any compound, its retention and efficiency, are kn…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Abhijit, Tarafder , Georges, Guiochon

In SFC, the key chromatographic parameters of any compound, its retention and efficiency, are known to strongly depend on the density of the mobile phase. This indicates that iso-density, also called isopycnic, plots drawn on the Pressure-Temperature plane can provide an effective tool to analyze how SFC systems may operate under different combinations of inlet and outlet pressures and column temperature. To effectively use these isopycnic plots in designing the operations of SFC systems, however, a deeper understanding of the factors behind the dependence of the performance of these systems on the mobile phase density is required. The nature of...

Ultra Resolution Chemical Fingerprinting of Dense Non-Aqueous Phase Liquids from Manufactured Gas Plants by Reversed Phase Comprehensive Two-Dimensional Gas Chromatography

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Laura A., McGregor , Caroline, Gauchotte , Niamh Nic, Daéid , Russell, Thomas , Paddy, Daly , …Ultra resolution chemical finger…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Laura A., McGregor , Caroline, Gauchotte , Niamh Nic, Daéid , Russell, Thomas , Paddy, Daly , ...

Ultra resolution chemical fingerprinting of dense non-aqueous phase liquids (DNAPLs) from former manufactured gas plants (FMGPs) was investigated using comprehensive two-dimensional gas chromatography coupled with time of flight mass spectrometry (GCxGC TOFMS). Reversed phase GCxGC (i.e. a polar primary column coupled to a non-polar secondary column) was found to significantly improve the separation of polycyclic aromatic hydrocarbons (PAHs) and their alkylated homologues. Sample extraction and cleanup was performed simultaneously using accelerated solvent extraction (ASE), with recovery rates between 76% and 97%, allowing fast, efficient extraction with minimal solvent consumption. Principal component analysis (PCA) of the GCxGC data was performed in...

Preparative separation of lithospermic acid B from Salvia miltiorrhiza by polyamide resin and preparative high-performance liquid chromatography

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Y.X., Guo , L.L., Zhou , T., LI , L.H., WangAdsorption on polyamide resin was investigated as a means of separating lithospermic ac…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Y.X., Guo , L.L., Zhou , T., LI , L.H., Wang

Adsorption on polyamide resin was investigated as a means of separating lithospermic acid B (LAB) from a crude extract of the roots of the traditional Chinese medicine Salvia miltiorrhiza Bunge (“Danshen”). Variables affecting adsorption capacity (solution pH, contact time on resin, initial LAB concentration) were studied. Adsorption was strongly dependent upon the initial concentration of LAB and pH. In all conditions, the polyamide resin gave optimal adsorption of LAB at an initial concentration of 2.66mg/mL and pH <3.0. The adsorption isotherm correlated well with the Langmuir-type adsorption isotherm. Maximal adsorption capacity was calculated to be 380mg/g at pH 2.0 and...

Development and validation of a pre-column reversed phase liquid chromatographic method with fluorescence detection for the determination of primary phenethylamines in dietary supplements and phytoextracts

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Rita, Gatti , Cinzia, LottiA sensitive and selective reversed-phase liquid chromatographic (RP-LC) method was developed and validated…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Rita, Gatti , Cinzia, Lotti

A sensitive and selective reversed-phase liquid chromatographic (RP-LC) method was developed and validated to determine octopamine, tyramine and Tyrosine (Tyr) in complex matrices as formulations and phytoextracts (Citrus aurantium), after pre-column derivatization with o-phthaldialdehyde (OPA) reagent. The chromatographic separations were performed at room temperature on a Phenomenex Luna C18 column using methanol and sodium acetate buffer (pH 5.5) by varying composition gradient elution as mobile phase and detected flurometrically at λem= 455nm with λex= 340nm. The results obtained by the proposed method were compared with those achieved by a validated direct RP-LC method with fluorescence detection at λem= 310nm with...

Enantioselective Analysis of Ibuprofen, Ketoprofen and Naproxen in Wastewater and Environmental Water Samples

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011Nor H., Hashim , Stuart J., KhanA highly sensitive and reliable method for the enantioselective analysis of ibuprofen, ketoprofen and…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 20 May 2011

Nor H., Hashim , Stuart J., Khan

A highly sensitive and reliable method for the enantioselective analysis of ibuprofen, ketoprofen and naproxen in wastewater and environmental water samples has been developed. These three pharmaceuticals are chiral molecules and the variable presence of their individual (R)- and (S)-enantiomers is of increasing interest for environmental analysis. An indirect method for enantioseparation was achieved by the derivatization of the (R)- and (S)-enantiomers to amide diastereomers using (R)-1-phenylethylamine ((R)-1-PEA). After initial solid phase extraction from aqueous samples, derivatization was undertaken at room temperature in less than 5minutes. Optimum recovery and clean-up of the amide diastereomers from the derivatization solution was achieved...

A rapid and environmental friendly determination of the dithiocarbamates metabolites ethylenethiourea and propylenethiourea in fruit and vegetables by Ultra High Performance Liquid Chromatography tandem Mass Spectrometry

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011Aurore, Bonnechère , Vincent, Hanot , Joris, Van LocoPrevious published methods for the analysis of ETU and PTU are time-consuming …

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011

Aurore, Bonnechère , Vincent, Hanot , Joris, Van Loco

Previous published methods for the analysis of ETU and PTU are time-consuming and furthermore use dichloromethane (DCM) for extraction or clean-up. This study details the development and validation of a rapid method that combines a simple extraction step with UHPLC-ESI+-MS/MS. This is the first application of UHPLC-MS/MS to analyse these compounds. Besides that, we replaced DCM with a more environmental-friendly solvent. The analytical performance was evaluated with the analysis of spiked celery samples at 50μgkg−1 (LOQ) and 300μgkg−1. The recoveries were between 65% and 90% for ETU and between 71% and 127% for PTU with RSDs in repeatability and reproducibility...

Use of isopycnic plots in designing operations of Supercritical Fluid Chromatography (SFC) II. The isopycnic plots and the selection of the3 operating pressure-temperature zone in SFC

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011Abhijit, Tarafder , Georges, GuiochonIn SFC, the key chromatographic parameters, the retention factors and the column effciency, stro…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011

Abhijit, Tarafder , Georges, Guiochon

In SFC, the key chromatographic parameters, the retention factors and the column effciency, strongly depend on the density of the mobile phase. This indicates that the isodensity or isopycnic plots, drawn on the pressure-temperature plane, can provide an effective tool to help analyzing how the chromatograms obtained in SFC evolve, when the experimental conditions, the inlet and outlet pressures and the column temperature, are changed. In a companion paper, we analyzed the role of density in controlling the physical properties of the mobile phase, which in turn controls solute retentions and column effciencies. In this report, we analyze the operating...

Accurate measurements of peak variances. Importance of this accuracy in the determination of the true corrected plate heights of chromatographic columns

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011Fabrice, Gritti , Georges, GuiochonThe true efficiency of a column is derived from the differences between the variances of the peak …

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011

Fabrice, Gritti , Georges, Guiochon

The true efficiency of a column is derived from the differences between the variances of the peak profiles of the same compound recorded in the presence and the absence of the chromatographic column. These variances are usually derived using one of three methods: (1) the retention time of the peak apex and its half-height width; (2) the moments of the best fit between the experimental data and a hybrid response function, e.g., an exponentially convoluted Gaussian; or (3) the exact moments of the experimental band profiles.Comparisons of the results of these methods show that the first method is always inaccurate...

Improved enantiomer resolution and quantification of free D-amino acids in serum and urine by comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011Magdalena C., Waldhier , Martin F., Almstetter , Nadine, Nürnberger , Michael A., Gruber , Katja, Dettmer , …The potential of c…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 19 May 2011

Magdalena C., Waldhier , Martin F., Almstetter , Nadine, Nürnberger , Michael A., Gruber , Katja, Dettmer , ...

The potential of comprehensive two-dimensional gas chromatography–time-of-flight mass spectrometry (GC×GC-TOFMS) in the quantitative analysis of amino acid enantiomers (AAEs) as their methyl chloroformate (MCF) derivatives in physiological fluids was investigated. Of the two column sets tested, the combination of an Rt-γDEXsa chiral column with a polar ZB-AAA column provided superior selectivity. Twenty AAEs were baseline resolved including L-Leu and D-Ile, which had failed separation by one-dimensional chiral GC-quadrupole-MS (GC-qMS). Lower limits of quantification (LLOQ) were in the range of 0.03–2μM. Reproducibility of the analysis of a serum specimen in octaplicate ranged from 1.3 to 16.6%. The GC×GC-TOFMS method was validated...

Optimized ultrasonic assisted extraction-dispersive liquid-liquid microextraction coupled with gas chromatography for determination of essential oil of Oliveria decumbensVent

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011Hassan, Sereshti , Yahya, Izadmanesh , Soheila, SamadiUltrasonic assisted extraction-dispersive liquid liquidmicroextraction (UAE–…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011

Hassan, Sereshti , Yahya, Izadmanesh , Soheila, Samadi

Ultrasonic assisted extraction-dispersive liquid liquidmicroextraction (UAE–DLLME) coupled withgas chromatography(GC) was applied for extraction and determination of essential oil constituents of the plantOliveria decumbensVent.Scanning electron microscopy (SEM)was used to see the effect of ultrasonic radiation on the extraction efficiency.By comparison with hydrodistillation,UAE-DLLME is fast, low cost, simple, efficientand consumingsmall amount of plant materials (∼1.0g). The effects of various parameters such as temperature, ultrasonication time, volume of disperser and extraction solventswereinvestigated by a full factorial designto identify significantvariables and their interactions.The resultsdemonstrated that temperature and ultrasonication time had no considerable effect on the results.In the next step, a central composite design (CCD)...

High-efficiency high performance liquid chromatographic analysis of red wine anthocyanins

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011André, de Villiers , Deirdre, Cabooter , Frédéric, Lynen , Gert, Desmet , Pat, SandraThe analysis of anthocyanins in natural pr…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011

André, de Villiers , Deirdre, Cabooter , Frédéric, Lynen , Gert, Desmet , Pat, Sandra

The analysis of anthocyanins in natural products is of significant relevance in recent times due to the recognised health benefits associated with their consumption. In red grapes and wines in particular, anthocyanins are known to contribute important properties to the sensory (colour and taste), anti-oxidant- and ageing characteristics. However, the detailed investigation of the alteration of these compounds during wine ageing is hampered by the challenges associated with the separation of grape-derived anthocyanins and their derived products. High performance liquid chromatography (HPLC) is primarily used for this purpose, often in combination with mass spectrometric (MS) detection, although conventional HPLC methods...

Solution cathode glow discharge induced vapor generation of mercury and its application to mercury speciation by high performance liquid chromatography-atomic fluorescence spectrometry

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011Qian, He , Zhenli, Zhu , Shenghong, Hu , Lanlan, JinA novel solution cathode glow discharge (SCGD) induced vapor generation was dev…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011

Qian, He , Zhenli, Zhu , Shenghong, Hu , Lanlan, Jin

A novel solution cathode glow discharge (SCGD) induced vapor generation was developed as interface to on-line couple high-performance liquid chromatography (HPLC) with atomic fluorescence spectrometry (AFS) for the speciation of inorganic mercury (Hg2+), methyl-mercury (MeHg) and ethyl-mercury (EtHg). The decomposition of organic mercury species and the reduction of Hg2+ could be completed in one step with this proposed SCGD induced vapor generation system. The vapor generation is extremely rapid and therefore is easy to couple with flow injection (FI) and HPLC. Compared with the conventional HPLC-CV-AFS hyphenated systems, the proposed HPLC-SCGD-AFS system is very simple in operation and eliminates auxiliary...

The Use of Silica Nanoparticles for Gas Chromatographic Separation

Publication year: 2011Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011Na, Na , Xianglan, Cui , Thomas, De Beer , Tingting, Liu , Tingting, Tang , …A new IL-dispersed silica nanoparticles (IL-SNs) ca…

Publication year: 2011
Source: Journal of Chromatography A, In Press, Accepted Manuscript, Available online 18 May 2011

Na, Na , Xianglan, Cui , Thomas, De Beer , Tingting, Liu , Tingting, Tang , ...

A new IL-dispersed silica nanoparticles (IL-SNs) capillary column, combining properties of silica nanoparticles and ionic liquid (IL), was used for gas chromatographic separation. By dispersing silica nanoparticles in a conventional IL of 1-butyl-3-methylimidazolium hexafluorophosphate ([BuMIm][BF6]), a layer of homogeneous interconnected particulate silica networks (thickness: 0.4 - 0.6μm) was formed on the inner surface of a capillary column. This coating integrates advantages of silica nanoparticles (high surface area, high dispersed behaviour) and IL (extended liquid-state temperature range, chemical stability), hence increasing interactions between stationary phase and analytes. It was demonstrated that mixtures of a wide range of organic compounds including alcohols,...