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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.

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.

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...

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.

In this work hydroxycinnamic acid esters of tartaric acid (mono-p-coumaroyl tartaric acid, monocaffeoyl tartaric acid, monoferuloyl tartaric acid esters) were separated, identified and quantified in several red wines by high performance liquid chromatography coupled with tandem mass spectrometry. The method features direct analysis of wines with no preparation and analysis of grape juice with minimum sample manipulation. For the identification was used both a triple quadrupole and a quadrupole–Tof, while for the quantification a triple quadrupole. At the same time two impurities, due to interfering substances coming from methanol (stored in bottles with polypropylene tops without Teflon protection), were characterised. These impurities had the same molecular weight as the investigated compounds.

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.

Stilbenes from grapes and wines play a central role in the human diet because of their antioxidant, antimutagenic and anticarcinogenic properties. We describe a method for the direct determination of some stilbenes (cis- and trans-resveratrol, cis- and trans-resveratrol glucoside, cis- and trans-piceatannol, and cis- and trans-piceatannol glucoside) in wine by high-performance liquid chromatography/mass spectrometry using a triple quadrupole (QqQ) mass spectrometer, in multiple reaction monitoring (MRM) mode, acquiring two diagnostic product ions from the chosen precursor. All the target analytes were separated on a C-18 column using gradient elution, in a single run. Electrospray ionization (ESI) in negative ion mode gives higher sensitivity for all the target compounds than atmospheric pressure chemical ionization (APCI). For the identification of piceatannol glucoside (astringin), because of the lack of a suitable standard, an HPLC/TOFMS method was used. The method permits direct injection of samples and it is time-saving, removing the need for sample pre-treatment. The detection limits were 48.0 ng mL(-1) for cis- and trans-resveratrol and for cis- and trans-resveratrol glucoside, and 50.0 ng mL(-1) for cis- and trans-piceatannol. The procedure proved to be simple and suitable for routine and confirmatory purposes. A total of 19 red and 3 white Italian wines were analyzed and differences in the stilbene composition were found among these samples.

Stanozolol is an anabolic steroid illicitly used for growth promoting purposes in animal production. For reasons of public health the use of anabolic steroids as growth promoters is officially banned in Europe in animals intended for consumption. The aim of this work is the investigation of stanozolol metabolites, 3′-hydroxystanozolol, 4β- hydroxystanozolol and 16β- hydroxystanozolol in urine samples after stanozolol administration to a young calf. After solid phase extraction of urine samples, detection is carried out by HPLC-MS-MS multiple reaction monitoring. Average recovery for the three metabolites is 80%. The method is highly specific and has been validated in terms of linearity, inter and intra day precision. In addition the decision limit CCα and the detection capability CCβ have been determined.

Biophenolic compounds constitute a complex mixture in olives and derived products. In this work, ion-spray tandem mass spectrometry coupled with liquid chromatography is applied to the identification and quantification of biophenols present in complex matrices such as olives and vegetation waters. The extraction and purification method for the biophenol present in both the matrices is reported. Using this approach the main biophenols found, in three different variety of olives, were: tyrosol, hydroxytyrosol, oleoside methyl ester, oleoside dimethyl ester, and oleuropein. In vegetation water the biophenols are present in lower amounts than in olives.

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 for the extraction and separation of the non-volatile phenolic acids of wine is described. The extracts are analysed by HPLC with a microbe column and UV detection. The free phenolic acids and depsides in different wine samples were identified and determined.

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.