Search

Methodology for detection of activated benzo[ a]pyrene (B[a]P)-nucleoside adducts by liquid chromatography-tandem mass spectrometry is reported. Adducts of B[a]P-dihydrodiol epoxide (B[a]PDE) with guanosine and adenosine have been detected for the first time by use of precursor ion scan and neutral loss scan. B[a]P was then activated by use of UV irradiation and some of the products obtained have been identified by taking advantage of the information obtained for B[a]PDE. Photoactivation has also been carried out in the presence of hydrogen peroxide; this resulted in a higher yield of products with increased production of BaP diones. The reactivity of these compounds toward nucleosides has been tested. The proposed method was successfully used for detection of one stable guanosine-B[a]P dione adduct. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

An analytical procedure for the simultaneous determination in human plasma and oral fluids of several illicit drugs belonging to different chemical and toxicological classes is presented. Amphetamine, methamphetamine, morphine, 6-monoacetylmorphine, methylenedioxyamphetamine, methylenedioxyethylamphetamine, methylenedioxymethamphetamine, cocaine, benzoylecgonine, tetrahydrocannabinol, carboxytetrahydrocannabinol, ketamine, and phencyclidine have been quantified in real samples using a very rapid sample treatment, basically a protein precipitation. The quantitative analysis was performed by liquid chromatography–tandem mass spectrometry and has been fully validated. All the analytes were detected in positive ionization mode using a TurboIonSpray source, except carboxytetrahydrocannabinol, which was detected in negative ionization mode. The use of a diverter valve between the column and the mass spectrometer allows the preservation of the ion source performances for high-throughput analysis. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In this paper an extraction procedure is presented for sulphonamides (SAs) in animal tissues (raw meat and meat-based baby food), based on matrix solid phase dispersion (MSPD). Determination was carried out using liquid chromatography coupled with tandem mass spectrometry. In complex matrices extraction is usually the critical step of analysis: several procedures were employed for the recovery of SAs in animal tissues, but often they entail time and solvent-consuming processes. MSPD has demonstrated itself to be a very efficient extraction technique for matrices such as animal tissues, with simplified and shortened procedures, and very low solvent consumption. This procedure allowed to obtain quantitative recovery, high selectivity improved by a cool eluant, and easy application. Good recoveries are accompanied by low RSDs and not a significative matrix effect. The MSPD procedure, coupled with LC-MS-MS analysis, provides very interesting LODs, due also to the concentration step. Validation is carried out following the EU guidelines for confirmation methods (EU Dec. 657/02). [ABSTRACT FROM AUTHOR]

An analytical method based on liquid chromatography–tandem mass spectrometry (LC-MS-MS) has been developed for the determination of pharmaceutical compounds in water samples. The drugs investigated were the analgesics: Ibuprofen, Fenoprofen, Ketoprofen, Naproxen, and Diclofenac and the decomposition product of acetylsalicylic acid: salicylic acid. The selected compounds are acidic, very polar and all are analgesic compounds that can be purchased without medical prescription. Sample enrichment of water samples was achieved by solid-phase extraction procedure (SPE), using Waters Oasis HLB cartridges followed by LC-MS-MS. A narrow-bore 2.1 mm i.d., reversed phase LC C-18 column was used to chromatograph analytes. Average recoveries from 1 L samples varied 75–95% and the detection limits are <1 ng L−1. The method developed was applied to real samples from wastewater and surface waters of Lazio country (Italy). [ABSTRACT FROM AUTHOR]

‘Free’ steroidal estrogens have been identified as compounds possibly responsible for endocrine-disruption of aquatic fauna populating rivers in which municipal sewage-treatment plants (STP) discharge their effluents. Natural and synthetic estrogens are excreted, as glucuronides and sulfates, by man, in the urine but these are bioconverted back to the unconjugated forms in wastewater discharges. For this reason we have developed a sensitive analytical procedure, without derivatization, for identification and quantitation of conjugated and free estrogens in surface and waste waters. The hormones were extracted and fractionated, by use of Carbograph cartridges, into neutral and acid fractions which were then analyzed by liquid chromatography-tandem mass spectrometry. Recoveries were between 66 and 100% and limits of detection ( LOD) between 15.0 and 0.003 ng L−1, depending on the compound and the water matrix. When this methodology was applied to real sewage and river water we could measure the main free estrogens at ng L−1 levels. Among the conjugates we always observed the presence of estrone 3-sulfate (at levels between 8.0 and 0.5 ng L−1). [ABSTRACT FROM AUTHOR]

The presence of 16 of the most widely used pesticides in southern Italy (plus atrazine, the use of which is currently restricted in Europe) has been monitored in ten surface waters of the Calabria Region. The analytes were extracted from water by off-line solid-phase extraction with a Carbograph cartridge. Base-neutral, and acid pesticides were then isolated by differential elution. Analyte fractionation and quantification were performed by liquid chromatography (HPLC) with UV detection. Recoveries of analytes from 0.5 L river water (200 ngL−1 spike level) were ≥84%. Confirmatory analysis was performed by HPLC coupled with ion-spray mass spectrometry (LC-ESI-MS). [ABSTRACT FROM AUTHOR]

Thermogravimetry (TG) and derivative thermogravimetry (DTG) are proposed as a fast and sensitive tool to discriminate the industrial processing of spaghetti pasta by focusing the attention on the thermal profiles of the structured water release. Thirteen different name-brand and store-brand kinds of spaghetti pasta were analysed. The results show different profiles according to the drying procedures. By on-line coupling a FTIR spectrometer to the thermobalance, the evolved gas analysis (EGA) allowed to confirm the water releasing step. [ABSTRACT FROM AUTHOR]