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Resveratrol (3,5,4′-trihydroxystilbene) is a phytoalexin that belongs to the group of stilbenes, known to occur in grapes and consequently in grape products. Its presence in wine is an important qualitative parameter because of the several beneficial effects on human health. The aim of this work is the development of a high-performance liquid chromatographic (HPLC) method for the determination of trans resveratrol in wines, and comparisons between the results obtained by different detection techniques: UV-vis spectroscopy, fluorescence spectroscopy and mass spectrometry. Resveratrol is analysed on a C-18 column using gradient elution. The method permits direct injection of sample, revealing to be time-saving, overcoming the need of sample pre-treatment steps. Detection limits were 154.8 ng mL−1 by HPLC-UV, 118.0 ng mL−1 by HPLC-FL and 48.0 ng mL−1 by HPLC-MS. Trans resveratrol has been then quantified in a group of 52 wines derived from different Italian regions, cultivars and winemaking technologies by HPLC-UV.

Boldenone is an androgenic anabolic steroid (AAS) intensively used for growth promoting purposes in animals destined for meat production and as a performance enhancer in athletics. Therefore its use is officially banned either in animals intended for consumption or in humans. Because most anabolic steroids are completely metabolized and usually no parent steroid is excreted, metabolite identification is crucial to detect the illegal use of anabolic steroids either in humans or in livestock. The aim of this work is the investigation of 17-boldenone and its main metabolites, 17-sulphate, 17-glucuronide, 5-androst-1-en17-ol-3-one and 17-boldenone, in human and bovine urine developing a multiresidue analysis. After solid phase extraction of urine samples, detection is carried out by high performance liquid chromatography–tandem mass spectrometry in multiple reaction monitoring. The average recovery for all the investigated compounds is above 70%. The developed method is very easy, quick and highly specific. Linearity, precision, decision limit and detection capability were also evaluated. © 2005 Elsevier B.V. All rights reserved.

An analytical procedure for the determination of natural steroids and their conjugates was developed and applied to bovine and human urine. Fifteen compounds (free and conjugated) after extraction by solid-phase were identified by liquid chromatography–tandem mass spectrometry (LC–MS–MS) in multiple reaction monitoring (MRM). Free and conjugated steroids were detected all together in the same chromatographic analysis respectively in positive and negative ionization. This procedure reveals to be time-saving, because it overcomes the need of further sample pre-treatment steps, such as enzymatic hydrolysis and derivatisation. The recovery for each compound was around 80%. Limit of detection of each steroid free or conjugated has been evaluated.

Selenium has been determined in different parts of the Lecythis ollaria (LO) plant (Venezuela) and the determination of its speciation has been achieved in fruit seeds. The study has been performed using different analytical techniques including inductively coupled plasma atomic emission spectrometry (ICP-AES), differential pulse cathodic stripping voltammetry (DPCSV), instrumental neutron activation analysis (INAA), high performance liquid chromatography (HPLC) and mass spectrometry (MS). Different parts of the plant (leaves, bark, capsules and seeds) were examined as well as the soil where LO was growing. Among different considered parts, seeds show the highest content in selenium (≅5 g kg −1 ) which is dependent on the maturation extent of the fruit. In seeds, about half of the total selenium content is soluble in water while the remaining is involved in protein structure. In the aqueous fraction, the prevailing form of selenium appears to be seleno-cystathionine with much lower amounts of Se(VI) and Se(IV).

In this work several compounds were detected in wines by HPLC-tandem mass spectrometry. In particular cinnamic and benzoic acids, tyrosol, apigenin-7-glucoside and luteolin-7-glucoside were identified and quantified in Italian wines. Red wines show bigger amount of cinnamic and benzoic acids than white wines. tyrosol is in bigger amount with respect to two flavones: luteolin-7-glucoside and apigenin-7-glucoside. These last two flavones are only in some wine, but it can be important to detect the presence of different substances in small amount to be able to characterize a wine.

This paper describes a method for analysing some acids of milk whey by Capillary Zone Electrophoresis. After eliminating the whey proteins by ultrafiltration, the whey underwent electrophoretic separation in the presence of anodic electroosmotic flow. The following analytes were detected: citric, orotic, uric, and hippuric acids. A procedure is described for sample preparation and the operating conditions for electrophoretic capillary separation established. Finally, orotic acid is quantitatively determined.

A liquid chromatographic–tandem mass spectrometric (LC–MS–MS) method has been developed for the determination of trenbolone in bovine urine and serum. The aim was a control of the misuse of trenbolone in food-producing animals. The procedure involved, in both cases, a preliminary solid-phase clean-up followed by a liquid–liquid extraction for urine samples after a preliminary enzymatic hydrolysis. The extracts have been directly analysed by reversed-phase LC–MS–MS in selected reaction monitoring (SRM), acquiring two diagnostic product ions from the chosen precursor [M+H] + . The procedures were validated across the concentration range of 1–1500 ng/ml. The linearity, the inter- and intra-day accuracy and precision have been determined. The procedure was specific and the accuracy values were better than 20% at the limit of quantitation of spiked samples. The limit of quantification (LOQ) and the limit of detection (LOD) were, respectively, 1 ng/ml and 350 pg/ml for urine and serum. According to the draft, SANCO/1805/2000, we determined the decision limit CC α and the detection capability CC β . The recovery values for urine ranged from 87 to 128%, and for plasma the recovery was 70±4%. The procedure proved to be simple and suitable for routine and confirmatory purposes such as those developed for residue studies.

A new class of phenolic compounds, hydroxy-isochromans, was found in different samples of extra-virgin olive oil. In particular, the presence of l-phenyl-6,7-dihydroxy-isochroman, 10 and 1-(3′-methoxy-4′-hydroxy)phenyl-6,7-dihydroxy-isochroman, 11 was demonstrated by comparison of the high performance liquid chromatography–mass/mass (HPLC–MS/MS) spectra of biophenolic samples from extra-virgin olive oils with those of compounds obtained by a reaction between hydroxytyrosol and the aromatic aldehydes, benzaldehyde and vanillin, respectively.

Corticosteroids can be illegally administered to cattle as growth promoting agents to improve meat production. We developed a liquid chromatography-atmospheric pressure ionization mass spectrometry-mass spectrometry (LC-MS-MS) method able to identify and quantify flumethasone, one of the most potent fluorinated synthetic corticosteroid, in serum and urine from treated calves. The analyte was purified from urine (conjugated and free, following enzymatic hydrolysis) and from serum by C18 solid-phase and liquid-liquid extractions, then analyzed by LC-MS-MS monitoring the product ions of an abundant precursor (SRM in negative ionization mode). Results on flumethasone residues in biological fluids in three calves treated at different levels are presented. This method allowed the detection of flumethasone in bovine urine and serum at the 30-pg/ml level.

The aim of this work was to analyze by HPLC-MS-MS natural biophenolic compounds in complex natural samples like olives and olive oils. Eleven benzoic and cinnamic acids, vanillin and other eight bi...

Melatonin content in pharmaceutical products was quantitatively determined by capillary electrophoresis within 4 min. Sample preparation required the simple dissolution in water and filtration. An internal standard was used a linear relationship between melatonin concentration andR(melatonin corrected peak area/I.S. corrected area) was obtained, withr 2>0.998. Separations were carried out in coated capillaries with a borate running buffer. The method showed an high precision with a RSD value for migration times of 0.3% for intra-day and 1.4% for inter-day measures (n=48). For theR parameter RSD was 2.9% and refers to seven consecutive runs of the same sample on the same day. Two commercially available pharmaceutical products containg melatonin were analyzed. The method offers an easy and accurate routine option.

We propose a simple and accurate method for CE quantitative determination of somatostatin in pharmaceutical preparations. The method is specific for somatostatin as indicated by the resolution between the analyte and the analogue peptides which differ from somatostatin by one aminoacid. The linearity range is from 0.02 to 0.35 mg/ml. The recovery of the somatostatin from a pharmaceutical product is about 100.0%.

Phenolic acids such as syringic, p-coumaric, vanillic, caffeic, 3,4-dihydroxybenzoic and gallic acid, which are present in wines and other alcoholic drinks, were determined by capillary electrophoresis using an uncoated fused-silica capillary. The optimum conditions for their separation were investigated. Examples of electropherograms of phenolic acids contained in some Italian wines are reported.

Free phenolic acids in Italian wines and a sherry were identified by high-performance liquid chromatography. The samples were concentrated and passed through a Sep-Pak C18 cartridge and the acids were recovered by elution with 2 ml of tetrahydrofuran. The separation was carried out by gradient elution on a reversed-phase column with methanol—water and phosphate buffer (pH 2.7). Detection was carried out 280 and 230 nm.

Some citrus essential oils were analyzed by HPLC with both microbore and standard columns in reversed and normal phase. Volatile and non-volatile fraction were investigated. In the non-volatile fraction some coumarins have been identified. Fractions are detected spectrophotometrically at 220 nm and 320 nm before and after evaporation of samples. Some components were also identified by LC/MS.

The ethereal extracts of wines, beer and vermouth were analysed by high-performance liquid chromatography. The following three characteristic peaks were first identified using GC-MS and then quantitatively determined: 5-hydroxy-methyl-2-furaldehyde, 2-(4-hydroxyphenyl)ethanol and 3-(2-hydroxyethyl)indole.

A method is proposed for the determination of polycyclic aromatic hydrocarbons(PAHs) in carbon blacks. The PAHs are extracted from the carbon black with benzene in a Soxhlet apparatus, purified by silica gel thin layer chromatography, weighed and analysed by gas and-or high-performances liquid chromatography. The total PAH and benzo[a]pyrene (BaP) concentrations in different types of carbon blacks and in different batches of the same carbon black were determined. It is shown that the distribution of the PAH fraction in different types of carbon blacks is almost the same but there are considerable differences in the total amount of the PAH fraction and the BaP concentration.

The preparation and characterization of laboratory made polymeric columns of Chromosorb 101 and Porapak Q are described, with reference to a PRP-1 column packed under the same conditions. Column parameters such as permeability, efficiency and peak asymmetry factor were calculated. The swelling propensity of the materials was measured and the dependence of peak shape on the type of organic solvent used was investigated. The efficiencies of Chromosorb 101 and Porapak Q columns were satisfactory but the spherical material PRP-1 gave better results. Porapak Q exhibited very good physical properties such as high rigidity and permeability. The swelding of polymers in acetonitrile is higher than in methanol, so a better column performance is obtained when acetonitrile is employed as the eluent.

Mineral waters can be characterized by high-performance liquid chromatographie analysis after an on-line trace enrichment of the organic fraction. The major components of these non-volatile organic substances are the humic compounds found at a wide range of concentration. Phenylindole has been identified and determined in mineral waters stored in plastic containers.

A procedure is reported for the determination in natural waters of the six polycyclic aromatic hydrocarbons (PAHs) listed by WHO as indicators of pollution. The method consists in continuous liquid—liquid extraction, separation of the PAH fraction by thin-layer chromatography and reversed-phase high-performance liquid chromatography with a spectrofluorimetric detector. The method has been applied to unfiltered samples of river and sea waters with PAH levels below 0.1 ng/l.

A method for the identification of cyclic glucans (cycloamyloses and cyclosophoraoses) in terms of the glycosidic linkage type and of the degree of polymerization (DP) using a reversed-phase 5-μm amine bonded silica column is proposed. The dependence of the logarithm of the capacity factors (log k ′) on the DP and on the structure of the cyclic oligosaccharides is established by comparing the chromatographic behaviour of β(1 → 2)- d -glucans (cyclosophoraoses) from two different Rhizobium strains with that of cycloamyloses and of mono- and disaccharides. The determination of the DP of the cyclosophoraoses was achieved by high-performance liquid chromatography (HPLC) of the partial hydrolysates of three collected peaks. HPLC experiments using cyclosophoraoses from Rhizobium meliloti SU-47 and Rhizobium trifolii TA-1 demonstrate that such microbial carbohydrates are mixtures of cyclic glucans with DP ranging from 17 to more than 33, in different proportions depending upon the bacterial source.

After dealing with the main structure-to-property relations for plastic materials, this article outlines the most important lines of development for polymers. As illustrations of the above concept a few examples of short-range application are given, subdivided into different industrial sectors.