Search results for "high-performance liquid chromatography"

Retention pharmacokinetic and pharmacodynamic parameter relationships of antihistamine drugs using biopartitioning micellar chromatography

2001

Abstract Antihistamines are drugs which act by competitive inhibition of the H1 or H2 histamine receptors. Little has been known about their clinical pharmacokinetics and biological responses until the last few years. In this paper, we propose quantitative retention–activity relationship, QRAR, models based on the retention data of antihistamines in a biopartitioning micellar chromatography (BMC) system using a Brij35 mobile phase for describing pharmacokinetic parameters such as half-life and volume of distribution, or the pharmacodynamic parameters, therapeutic plasma levels, lethal doses and drug-receptor dissociation constant. The predictive ability of these models is statistically vali…

Determination of 5-nitrofurylacrylic acid in wines by high-performance liquid chromatography

1988

HPLC determination of volatile phenols in wines

1993

An alternative to the traditional solvent extraction method used to extract and rapidly quantify ethyl-and vinylphenol and ethyl-and vinylgaiacol from wine is presented. The method is based on retention of volatile phenols on adsorbants. Among the tested resins, the most efficient, AG 2-X8 (anion exchange resin), worked as well with a synthetic solution as with wines. The percolation of clarified wine adjusted to pH 9 on this resin permits, in particular, the elimination of organic acids. Phenols are not eluted after rinsing the column with 1N HCl, but are eluted with methanol after this treatment. Good recovery (91 %) and good repeatability are observed. The eluate is directly analysed by …

Quantitative determination of sotolon in wines by high-performance liquid chromatography

1993

Sotolon (4,5-dimethyl-3-hydroxy-2(5H)-furanone) is a key flavour compound in the french flor-sherry “Vin jaune”. This compound was determined quantitatively by extraction of 25 ml of wine on a XAD-4 resin, elution with diethyl ether, separation by HPLC on a Lichrospher 100 Diol column, elution with dichloromethane/hexane (60/40) and UV detection at 232 nm. The amount of sotolon in “Vin jaune” (120 to 268 μg/l) was related to the development of the yeast film over a period of 6 years. Only 6 to 51 μg/l were found in the “Vin de paille” which is made with overmaturated grapes of the same Savagnin vine-plant but without development of yeasts, and 80 to 140 μg/l in “Tokai” which are partly grow…

High Performance Liquid Chromatography Analysis of Grape and Wine Polyphenols

2008

Integrating analytical resolutions in non-targeted wine metabolomics

2015

Direct injection Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS), and ultra-high performance liquid chromatography coupled to mass spectrometry (UPLC/MS) were combined for the non-targeted analysis of wine metabolites. The unrivalled resolution on mass measurement allowed by the former and the separation ability of isomeric and isobaric substances by the latter, clearly increases the scope of detectable unknown metabolites in wines. Such methodology is illustrated through the comparison of chemical spaces of a young and an older Pinot noir wine. RP and HILIC chromatography could reveal up to five isomers for a given mass, throughout the explored mass range. CHO, CHOS …

Concentration of ochratoxin A in wines from supermarkets and stores of Valencian Community (Spain)

2004

Ochratoxin A (OTA) is a mycotoxin produced by fungi species belonging to the genera Aspergillus and Penicillium being isolated in alcoholic beverages. The aim of this work is developed and applied a procedure for the analysis of OTA in wines. An analytical method based on immunoaffinity column (IAC) for clean-up, liquid chromatography with fluorescence detection (LC-FD), and LC-FD after of OTA methylation was used to determine the occurrence of OTA in wines. Recoveries of this mycotoxin spiked to red wines at 0.5 ng/ml level were >90% with an average of relative standards deviations of 4%. Furthermore, 116 wine samples from designation of origin (DO) and three samples from food stores of Va…

The use of core-shell high-performance liquid chromatography column technology to improve biogenic amine quantification in wine

2015

BACKGROUND HPLC column technology has been improved, providing better resolution of closely eluting compounds, better analyte sensitivity, and shorter analysis times. The core-shell technology columns offer a faster analysis through the use of shorter columns without compromising resolution. The aim of this work was to improve the methods for determination of biogenic amines (BAs) in wine using the new HPLC PFP core-shell column technology. RESULTS Two different elution programs were designed to quantify BAs with the core-shell PFP column. Program I flow rate was 2 mL min−1. The total elution time was 10 min. In elution program II, the flow rate was 0.8 mL min−1 and the total elution time w…

Purification method for the isolation of monophosphate nucleotides from Champagne wine and their identification by mass spectrometry

2001

Monophosphate nucleotides are difficult to identify in Champagne wine because they are present in small concentrations in a complex mixture. A method for the isolation, separation and identification of reference compounds, which achieved on average 79% recovery (except for cytidine derivatives), was developed and applied to wine. Some monophosphate nucleotides were then isolated from a Champagne wine aged on lees for 8 years, by ultrafiltration followed by a semi-preparative HPLC step using a strong anion-exchange column. The fraction obtained was subjected to HPLC in a reversed-phase column to remove the salt previously introduced, before identification of compounds by HPLC coupled to a ma…

Applications of liquid chromatography-mass spectrometry for food analysis.

2012

Abstract HPLC–MS applications in the agrifood sector are among the fastest developing fields in science and industry. The present tutorial mini-review briefly describes this analytical methodology: HPLC, UHPLC, nano-HPLC on one hand, mass spectrometry (MS) and tandem mass spectrometry (MS/MS) on the other hand. Analytical results are grouped together based on the type of chemicals analyzed (lipids, carbohydrates, glycoproteins, vitamins, flavonoids, mycotoxins, pesticides, allergens and food additives). Results are also shown for various types of food (ham, cheese, milk, cereals, olive oil and wines). Although it is not an exhaustive list, it illustrates the main current directions of appli…