Determination of levamisole in feeds by liquid chromatography coupled to electrospray mass spectrometry on an ion trap.

Test methods have to be developed by laboratories for official control to monitor possible misuse of veterinary drugs in animal productions, also through feeding stuff. A novel method for identification and quantification of levamisole in feeds by liquid chromatography coupled to electrospray mass spectrometry in an ion trap (LC/ESI-MS/MS) is herein described; after a single-step cleanup by liquid-liquid extraction from the feed and separation by reversed-phase liquid chromatography, levamisole was determined and unambiguously confirmed by tandem mass spectrometry, on the basis of two product ions. The method was in-house validated, according to the Regulation 882/2004/EC, evaluating trueness, repeatability, within-laboratory reproducibility, ruggedness, specificity, and the limit of quantification (LOQ).

Palytoxin in seafood by liquid chromatography tandem mass spectrometry: investigation of extraction efficiency and matrix effect.

Blooms of Ostreopsis spp. have been recently reported along the Mediterranean coasts of Spain, France, Italy, and Greece posing serious risks to human health. Occurrence of Ostreopsis spp.

A peptidomic approach for monitoring and characterising peptide cyanotoxins produced in Italian lakes by matrix-assisted laser desorption/ionisation and quadrupole time-of-flight mass spectrometry.

In recent years, the occurrence of cyanobacterial blooms in eutrophic freshwaters has been described all over the world, including most European countries. Blooms of cyanobacteria may produce mixtures of toxic secondary metabolites, called cyanotoxins. Among these, the most studied are microcystins, a group of cyclic heptapeptides, because of their potent hepatotoxicity and activity as tumour promoters.

New palytoxin-like molecules in Mediterranean Ostreopsis cf. ovata (dinoflagellates) and in Palythoa tuberculosa detected by liquid chromatography-electrospray ionization time-of-flight mass spectrometry.

A rapid, high resolution liquid chromatography coupled with ElectroSpray Ionization Time-Of-Flight Mass Spectrometry (ESI/TOF/MS) method was developed for the determination of the toxin pattern in cultured cells of Ostreopsis cf. ovata from the Mediterranean Sea. The samples were separated on a Phenomenex Luna 3μ HILIC 200A (150 × 2.

Confirmatory analysis of non-steroidal anti-inflammatory drugs in bovine milk by high-performance liquid chromatography with fluorescence detection.

HPLC with fluorescence detection is considered for confirmatory analysis of group B veterinary drugs by the European Union legislation. A procedure for confirming the presence of anti-inflammatory non-steroidal drug (NSAID) residues in bovine milk by reversed phase high-performance liquid chromatography with fluorescence detection is herein described. The native fluorescence of nine drugs belonging to different NSAID sub-classes, namely flurbiprofen, carprofen, naproxen, vedaprofen, 5-hydroxy-flunixin, niflumic acid, mefenamic acid, meclofenamic acid and tolfenamic acid, allowed for detection in bovine milk down to 0.

Determination of the banned growth promoter moenomycin A in feed stuffs by liquid chromatography coupled to electrospray ion trap mass spectrometry.

Flavomycin complex is an antibiotic banned in the European Union as an additive in feed stuffs. As a consequence, the monitoring programmes for official control within the Community require analysis of feeds for possible illegal use of flavomycin. A method for unambiguous identification and quantification of moenomycin A, the main pharmacologically active component of flamomycin complex, in several feeds by liquid chromatography coupled to electrospray ion trap mass spectrometry (LC/ESI-MS/MS) is herein described for the first time.

Contamination levels and congener distribution of PCDDs, PCDFs and dioxin-like PCBs in buffalo's milk from Caserta province (Italy).

An extraordinary plan of official control was carried out in 2008 in Campania (Italy) with the aim to monitor polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) levels in buffalo milk and to detect the contaminated farms, most of which are located in Caserta province. For these companies has been ordered seizure and execution of additional analyses has been requested in farms falling in the nearness, within a distance of 3km, for a total of 304 farms examined. Moreover, all non-compliant farms were subjected to a periodic sampling in order to monitor trends in the levels of contamination.

Determination of cylindrospermopsin in freshwaters and fish tissue by liquid chromatography coupled to electrospray ion trap mass spectrometry.

Cylindrospermopsin (CYN) is a toxic alkaloid-like compound produced by some strains of cyanobacteria, procariotic organisms occurring in water blooms, observed worldwide in eutrophic lakes and drinking water reservoirs. Methods for determination of CYN in freshwater and fish muscle by liquid chromatography coupled to electrospray ion trap mass spectrometry are herein described. The performances of both methods are reported; ion trap LC/ESI-MS/MS resulted highly selective and reliable in unambiguous identification of CYN, based on monitoring the precursor ion and three product ions.

Characterisation of biotoxins produced by a cyanobacteria bloom in Lake Averno using two LC-MS-based techniques.

Cyanobacteria (blue-green algae) cause blooms in eutrophic lakes and drinking water reservoirs. They also produce biotoxins, including microcystins (MCs), highly toxic cyclic heptapeptides that cause poisoning in animals and human. In this paper, we present a method for the analysis of four MCs by ion trap LC-MS and MALDI-TOF/MS.

Liquid chromatography coupled to quadruple time-of-flight tandem mass spectrometry for microcystin analysis in freshwaters: method performances and characterisation of a novel variant of microcystin-RR.

Cyanobacteria, also called blue-green algae, occur worldwide within water blooms in eutrophic lakes and drinking water reservoirs, producing several biotoxins (cyanotoxins). Among these, microcystins (MCs) are a group of cyclic heptapeptides showing potent hepatotoxicity and activity as tumour promoters. So far, at least 89 MCs from different cyanobacteria genera have been characterised.

An analytical strategy for identification of a somatotropin-like bioactive peptide by ion trap liquid chromatography/electrospray ionization tandem mass spectrometry after immuno-affinity purification from buffalo serum.

The use of growth hormones, such as native and recombinant somatotropins, is forbidden in the European Union (EU), but is legal in the USA. The misuse of recombinant bovine somatotropin in Italy is suspected for enhancing milk production, thanks to its availability on the illegal market. A synthetic bioactive peptide of 27 amino acids derived from bovine somatotropin was successfully tested in France and in southern Italy for scientific purposes, to stimulate milk production, both in cows and buffaloes.

Modeling of DR CALUX bioassay response to screen PCDDs, PCDFs, and dioxin-like PCBs in farm milk from dairy herds.

A recent issue in the EU legislation is the evaluation of the toxicologically-equivalent contribution of dioxin-like polychlorobiphenyls (DL-PCBs) in addition to that coming from polychlorodibenzodioxins (PCDDs) and polychlorodibenzofurans (PCDFs) as contaminants in foods for a total of 29 congeners. This fact is determining the need to revise analytical criteria both for confirmatory and screening analysis. In this work, a modeling was developed to check the reliability of the outcomes of the DR CALUX bioassay when applied to farm milk samples characterized by large differences in congener patterns.

Confirmatory identification of sixteen non-steroidal anti-inflammatory drug residues in raw milk by liquid chromatography coupled with ion trap mass spectrometry.

The European Council Decision 2002/657/EC established that group B substances detected in foods must be identified and confirmed on the basis of their molecular structure. To this aim, we have developed a panel of methods for unambiguous determination of sixteen non-steroidal anti-inflammatory drugs (NSAIDs) in cattle and buffalo raw milk. A multi-residue reversed-phase high-performance liquid chromatography method with photodiode array detection is described for quantitative screening analysis.

The use of plasmatic acceptors as specific ligands in affinity chromatography cleanup of veterinary drugs from biological matrices.

Bovine alpha(1)-acid glycoprotein (bAAG) and bovine serum albumin (BSA) are plasmatic acceptors working as carriers by the specific and reversible binding of several drugs in vivo. We synthesized affinity columns by coupling bAAG and BSA to an activated chromatographic support through their carbohydrate moieties, to preserve protein tertiary structure and, consequently, to improve the biological activity in vitro. The bAAG and BSA affinity columns were used to study the binding of acidic and basic drugs.

Purification of clenbuterol-like beta2-agonist drugs of new generation from bovine urine and hair by alpha1-acid glycoprotein affinity chromatography and determination by gas chromatography-mass spectrometry.

The control of illegal use of clenbuterol and other beta(2)-agonist drugs as growth promoters in the European Union countries has led to outlaw practices for synthesizing new concept molecules, showing similar biological activity but not detectable by test methods usually employed to perform the official monitoring programmes. The synthesis schemes of some beta(2)-agonist compounds, formally derived from clenbuterol, were found out by Italian detective authorities. These compounds were synthesised ex novo in our laboratories: then, both their molecular structures and biological activities were characterised.

Multi-residue determination of non-steroidal anti-inflammatory drug residues in animal serum and plasma by HPLC and photo-diode array detection.

The European Union regulated the use of non-steroidal anti-inflammatory drugs (NSAIDs) in animal production and set the official analytical controls to detect their residues in plasma, serum, and milk within the frame of national monitoring programs in each member state. In this work, a multi-residue reversed-phase high-performance liquid chromatography with diode array detector (DAD) method is described for the simultaneous determination of 13 NSAIDs in serum and plasma of farm animals. Chromatographic separation by a C12 stationary phase column with a linear gradient is able to resolve all the compounds considered: salicylic acid, ketoprofen, flurbiprofen, phenylbutazone and its metabolite (oxyphenbutazone), carprofen, ibuprofen, naproxen, niflumic acid, suxibutazone, diclofenac, mefenamic acid, and tolfenamic acid.

Determination of fourteen non-steroidal anti-inflammatory drugs in animal serum and plasma by liquid chromatography/mass spectrometry.

The European Union has regulated the use of non-steroidal anti-inflammatory drugs (NSAIDs) in animal production and requires its member states to detect their residues in different matrices. In this work, a detailed MS and MS/MS study by ion-trap mass spectrometry of fourteen NSAIDs is described. Two multi-residue reversed-phase LC/ESI-MS/MS methods were developed, one for the determination of salicylic acid, naproxen, carprofen, flurbiprofen, ibuprofen, niflumic acid and meclofenamic acid in the negative ion mode, and the other for the determination of ketoprofen, suxibutazone, diclofenac, mefenamic acid, tolfenamic acid, phenylbutazone and its metabolite oxyphenbutazone in the positive ion mode.

In-house validation of a liquid chromatography/electrospray tandem mass spectrometry method for confirmation of chloramphenicol residues in muscle according to Decision 2002/657/EC.

In this work we present an in-house validation study for the confirmatory analysis of chloramphenicol (CAP) in muscle according to the Commission Decision 2002/657/EC requirements. CAP is extracted in acetonitrile and after liquid-liquid partitioning with n-hexane is identified and quantitatively determined by ion trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) analysis in the negative ion mode. CAP was identified using the precursor ion and at least two product ions, meeting the qualitative and quantitative criteria set by the European Commission in the Decision 2002/657/EC for confirmation of prohibited veterinary drug residues.

Development of a liquid chromatography/electrospray tandem mass spectrometry method for confirmation of chloramphenicol residues in milk after alfa-1-acid glycoprotein affinity chromatography.

In this work we present a method for confirmatory analysis of chloramphenicol (CAP) in bovine and buffalo raw milk. CAP is extracted in acetonitrile and purified by affinity chromatography on an alpha-1-acid glycoprotein (AAG) column, then is identified and determined by ion-trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) analysis in the negative ion mode. CAP was identified at the minimum required performance limit (MRPL) of 0.

Residue study of ivermectin in plasma, milk, and mozzarella cheese following subcutaneous administration to buffalo (Bubalus bubalis).

The distribution of ivermectin in buffalo plasma and milk after administration of a single subcutaneous dose (0.2 mg kg(-)(1) b.w.