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1.
Molecules ; 28(1)2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36615575

RESUMEN

Furosemide (FUR), an active pharmaceutical ingredient (API) belonging to a group of drugs known as loop diuretics, has widespread use, but, is characterized by a strong instability to light, which causes chemical transformations that could give a yellowing phenomenon and have a significant impact from a health and marketing point of view. Many studies have tried to explain this phenomenon under different experimental conditions, but no detailed explanation of the yellowing phenomenon has been provided. This work, unlike the others, provides an overall view and explanation of the behavior of FUR in relation to the yellowing phenomenon, both in the solution and in solid state, considering several aspects, such as light exposure, presence of oxygen, and moisture effects.


Asunto(s)
Diuréticos , Furosemida , Furosemida/química , Diuréticos/farmacología , Diuréticos/química , Antihipertensivos/farmacología , Oxígeno
2.
Rapid Commun Mass Spectrom ; 32(21): 1831-1842, 2018 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29943476

RESUMEN

RATIONALE: Carry-over is an undesirable contamination from medicated to non-medicated during the production of feedingstuffs. In 2014 the European Parliament and the Council started working to produce a new regulatory act that will fix tolerable levels of drugs by carry-over in non-target feed to have a harmonized practice to evaluate this contamination by veterinary drugs. METHODS: We developed a rapid and effective multi-analyte method coupling ultraperformance liquid chromatography to tandem mass spectrometry (UPLC/MS/MS) for the detection of 37 drugs belonging to different classes of antimicrobials (sulfonamides, tetracyclines, macrolides, quinolones, pleuromutilins and streptogramins) in feeds at carry-over levels. The method was in-house validated in the concentration range 0.25-2.0 mg kg-1 , according to the Regulation (UE) 2017/625 requirements and the guideline included in the Commission Decision 2002/657/EC for official methods. RESULTS: The UPLC/MS/MS method allows the determination of the antimicrobials in 15 min, by providing results compliant to the criteria established by the European Commission legislation. All the analytes showed a limit of detection (LOD) in the range 2.0-5.0 µg kg-1 and a limit of quantification (LOQ) at 10.0 µg kg-1 ; oxytetracycline, doxycycline, spiramycin and virginiamycin have a higher LOD and LOQ (15.0 µg kg-1 ; 30.0 µg kg-1 , respectively). Recoveries were satisfactory ranging from 90.4% to 103.1%. CONCLUSIONS: The method is characterized by an effective clean-up of all drugs without the use of large sample size and organic solvent extraction.


Asunto(s)
Alimentación Animal/análisis , Antibacterianos/análisis , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Drogas Veterinarias/análisis , Animales , Contaminación de Alimentos/prevención & control , Límite de Detección
3.
Bull Environ Contam Toxicol ; 92(6): 662-6, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24615507

RESUMEN

A simple, sensitive and rapid liquid chromatography-tandem mass spectrometry method (LC-MS/MS) was developed and validated to monitor the presence of gabapentin as environmental contaminant in albumen and yolk of eggs from grazing flocks exposed to open air stored saline wastes from pharmaceutical industry. The method involved a simple liquid extraction followed by a gradient elution with formic acid 0.2 % and acetonitrile in reverse phase. ESI ionization was performed in positive ion mode. The tandem mass spectrometer was operated in multiple reaction monitoring mode. The calibration curves were linear in the concentration range from 5 to 400 ng/g for the two matrices with correlation coefficients that exceeded 0.990. The limits of quantitation were 12.0 and 14.8 ng/g in albumen and yolk, respectively. Results are discussed in light of the pharmacokinetics of gabapentin in experimentally exposed hens, accounting for the top soil intake in such free grazing animals.


Asunto(s)
Aminas/análisis , Ácidos Ciclohexanocarboxílicos/análisis , Huevos/análisis , Residuos Industriales/análisis , Contaminantes del Suelo/análisis , Ácido gamma-Aminobutírico/análisis , Analgésicos , Animales , Pollos , Industria Farmacéutica , Femenino , Gabapentina , Herbivoria
4.
Rapid Commun Mass Spectrom ; 24(7): 1017-24, 2010 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-20213675

RESUMEN

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. The method was developed to be used as a confirmative analytical tool for the network of Italian official control laboratories; both the singly and doubly charged molecular ions were observed as precursor ions, from which four product ions were selected for both quantitative analysis and unambiguous identification of moenomycin A. The method was in-house validated for feeds in the concentration range 0.50-30.0 microg/g, according to the Regulation 882/2004/EC requirements. Mean recoveries ranging between 83.9-94.2% and relative standard deviations <23% account for method trueness and repeatability, respectively. Moreover, other analytical performance parameters, i.e. method specificity, ruggedness, the linearity of detector response, the limit of quantification (LOQ), the limit of detection (LOD), and measurement uncertainty were evaluated and reported. The ion trap LC/ESI-MS/MS method is highly selective and reliable; high drug recovery, good reproducibility and an LOQ down to 0.10 microg/g guarantee its applicability for confirmatory purposes in the official control activity in Italy.


Asunto(s)
Alimentación Animal/análisis , Bambermicinas/análisis , Cromatografía Liquida/métodos , Espectrometría de Masa por Ionización de Electrospray/métodos , Alimentación Animal/normas , Bambermicinas/química , Italia , Modelos Lineales , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Artículo en Inglés | MEDLINE | ID: mdl-18644750

RESUMEN

A new LC-MS/MS method for the separation, identification and quantification of residues of 17alpha-estradiol (17alpha-E2) and 17beta-estradiol (17beta-E2) in bovine serum is reported. Deuterium-labelled 17beta-estradiol was used as internal standard. The method was in-house validated in accordance with European Union criteria and adopted in a proficiency study organised by the Community Reference Laboratory (CRL-RIVM, Bilthoven, The Netherlands). The analytes were extracted from serum using acetate buffer, purified by C18 solid-phase extraction (SPE) and chromatographed on a C18 LC column. They were then ionized in a heated nebulizer (HN) interface operating in negative ion mode, where only intact deprotonated molecules, [M-H](-), were generated at m/z 271 and 274 for 17alpha/17beta-E2 and 17beta-E2-d(3), respectively. The decision limits obtained (CCalpha, i.e., critical concentration alpha) were 0.06 ng/mL and 0.03 ng/mL, respectively for 17alpha-E2 and 17beta-E2. Detection capability (CCbeta, i.e., critical concentration beta) values were 0.08 ng/mL and 0.04 ng/mL, respectively, for 17alpha-E2 and 17beta-E2. Precision, accuracy and specificity were satisfactory, recovery ranged from 86.3% to 93.2% and the method resulted sensitive for the required purposes. This method is currently in use for Official Control purposes.


Asunto(s)
Cromatografía Liquida/métodos , Estradiol/sangre , Espectrometría de Masas en Tándem/métodos , Animales , Bovinos , Estereoisomerismo
6.
Anal Bioanal Chem ; 391(4): 1153-62, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18193407

RESUMEN

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. Moreover, a purification strategy was developed for the cleanup of drug residues from biological matrices and foods, prior to screening and/or confirmatory analysis, on the basis of the specific molecular recognition between the protein and the drug. The aim of this work was to test the potency of bAAG- and BSA-based affinity chromatography to bind some veterinary drugs and purify them in the context of the official control of animal products. The efficiency of these homemade affinity columns in minimising matrix interference and in selective cleanup of different classes of substances was reported and discussed.


Asunto(s)
Cromatografía de Afinidad/métodos , Orosomucoide/metabolismo , Albúmina Sérica Bovina/metabolismo , Drogas Veterinarias/aislamiento & purificación , Drogas Veterinarias/metabolismo , Animales , Bovinos , Cromatografía de Afinidad/instrumentación , Cromatografía Líquida de Alta Presión , Residuos de Medicamentos/aislamiento & purificación , Ligandos , Hígado/metabolismo , Espectrometría de Masas , Orosomucoide/química , Estándares de Referencia , Sensibilidad y Especificidad , Albúmina Sérica Bovina/química , Solventes
7.
Food Chem Toxicol ; 45(9): 1694-9, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17449161

RESUMEN

Beta(2)-receptor adrenergic agonists as clenbuterol and analogues are illegally used as growth promoters in cattle, in Europe, as well as in other countries. Following consumption of meat or liver, intoxication cases were described, and cardiovascular toxic effects (tachycardia, hypertension) were of clinical relevance. Therefore, we investigated whether heart rate increase induced by clenbuterol could depend upon stimulation of beta(1)- and/or beta(2)-adrenergic receptors, and in which ratio. We used in vitro guinea-pig atria, a model in which beta(1)-/beta(2)-receptors ratio is similar to that found in men. In our experiments both beta(1)- and beta(2)-receptors contributed to clenbuterol-induced heart rate increase, but with a different potency. The selective beta(2)-antagonist ICI-118,551 competitively antagonized responses to clenbuterol with high affinity (pA(2) 9.47+/-0.28, SchildSlope 0.98+/-0.20 not significantly different from unity, K(B) 0.34 nM). The selective beta(1)-antagonist atenolol antagonized clenbuterol with a relatively lower affinity (pA(2)=7.59+/-0.14), the SchildSlope=1.97+/-0.33 was significantly different from unity (P<0.05). Results show that clenbuterol stimulates guinea-pig heart rate by acting chiefly on beta(2)-adrenoceptor, although responses to clenbuterol apparently are mediated by an inter-play between both beta-adrenoceptors. Further experiments are necessary to understand which beta-adrenergic antagonists are of effectiveness to counteract cardiovascular effects in case of intoxication following clenbuterol, or other beta-adrenergic stimulants.


Asunto(s)
Agonistas Adrenérgicos beta/toxicidad , Clenbuterol/toxicidad , Receptores Adrenérgicos beta 1/metabolismo , Receptores Adrenérgicos beta 2/metabolismo , Taquicardia/inducido químicamente , Agonistas Adrenérgicos beta/farmacocinética , Animales , Función Atrial/efectos de los fármacos , Clenbuterol/farmacocinética , Relación Dosis-Respuesta a Droga , Contaminación de Alimentos , Cobayas , Atrios Cardíacos/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Humanos , Masculino , Receptores Adrenérgicos beta 1/efectos de los fármacos , Receptores Adrenérgicos beta 2/efectos de los fármacos
8.
Front Immunol ; 8: 1813, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29312324

RESUMEN

Toll-like receptor (TLR)7/8 plays a crucial role in host recognition/response to viruses and its mucosal expression directly correlates with intestinal inflammation. The aim of this study was to investigate the role of TLR7/8 stimulation of intestinal epithelium in shaping the phenotype and functions of innate immunity cell subsets, and to define direct and/or epithelial cell-mediated mechanisms of the TLR7/8 agonist R848 immunomodulatory activity. We describe novel, TLR8-mediated, pro- and anti-inflammatory effects of R848 on ex vivo cultured human blood monocytes and γδ T lymphocytes, either induced by direct immune cell stimulation or mediated by intestinal epithelial cells (IEC). Apical stimulation with R848 led to its transport across normal polarized epithelial cell monolayer and resulted in the inhibition of monocyte differentiation toward immunostimulatory dendritic cells and Th1 type response. Furthermore, γδ T lymphocyte activation was promoted following direct exposure of these cells to the agonist. Conversely, a selective enrichment of the CD14+CD16+ monocyte subpopulation was observed, which required a CCL2-mediated inflammatory response of normal epithelial cells to R848. Of note, a TLR-mediated activation of control γδ T lymphocytes was promoted by inflamed intestinal epithelium from active Crohn's disease patients. This study unravels a novel regulatory mechanism linking the activation of the TLR8 pathway in IEC to the monocyte-mediated inflammatory response, and highlights the capacity of the TLR7/8 agonist R848 to directly enhance the activation of γδ T lymphocytes. Overall these results expand the range of cell targets and immune responses controlled by TLR8 triggering that may contribute to the antiviral response, to chronic inflammation, as well as to the adjuvant activity of TLR8 agonists, highlighting the role of intestinal epithelium microenvironment in shaping TLR agonist-induced responses.

9.
J Chromatogr Sci ; 44(10): 585-90, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17254366

RESUMEN

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. These compounds are chosen as the most representative of the different NSAID chemical sub-classes. The DAD analysis allows the confirmation of all drugs on the basis of their own UV-vis spectrum, according to the requirements of the European Council Decision 2002/657/EC. Moreover, the method is in-house validated, evaluating mean recoveries, specificity, repeatability, and within-laboratory reproducibility as the performance parameters required by the Decision. The results of this study indicate the method is specific and repeatable, with the mean percentage recoveries of the drugs ranging between 72.5% and 104.5%. Only salicylic acid has poor recovery, with results ranging between 36.3% and 54.9%.


Asunto(s)
Antiinflamatorios no Esteroideos/sangre , Cromatografía Líquida de Alta Presión/métodos , Residuos de Medicamentos/análisis , Animales , Bovinos , Caballos , Fotoquímica , Reproducibilidad de los Resultados , Porcinos
10.
Redox Rep ; 7(3): 159-63, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12189046

RESUMEN

In pigs, the genetic selection for lean, large muscle blocks and fast growth has been linked to an increased prevalence of metabolic diseases such as porcine stress syndrome and mulberry heart disease. These diseases are associated with cardiovascular inadequacy, which may lead to oxidative stress. In the present study, reactive oxygen metabolites (ROMs) and the anti-oxidant power (OXY) in sera of different swine groups were investigated. The following groups were selected (each around 80 kg body weight): wild boars (WB), Cinta Senese (CS), and Landrace x Large White (LxLW), the latter as both specific pathogen-free (SPF) and intensively farmed animals. In addition, a group of LxLW agonic sows (AS) was also investigated; this group is known to be under oxidative stress. Two colorimetric micro-methods were used to measure ROMs and OXY; ROMs were expressed as mM H(2)O(2) and OXY as microM HOCl neutralised. Between groups, average ROM and OXY values were found to be significantly different by one-way ANOVA (P < 0.001). ROM levels were lower in WB (13.41 +/- 1.85) and CS (19.27 +/- 1.68), and highest in LxLW (42.00 +/- 1.36). OXY values ranged from 260.10 +/- 22.13 (WB) to 396.90 +/- 9.83 (LxLW). Only one swine group (the CS group) showed a significant, positive correlation between ROM and OXY values. The AS group even showed a negative correlation between ROM and OXY values. These results imply satisfactory environmental coping occurred only within the CS group. Results are discussed in the light of animal welfare legislation, food safety and consumers' protection.


Asunto(s)
Estrés Oxidativo/fisiología , Porcinos/fisiología , Bienestar del Animal , Animales , Animales Domésticos , Animales Salvajes , Músculo Esquelético/fisiología , Oxidación-Reducción
11.
Artículo en Inglés | MEDLINE | ID: mdl-15093162

RESUMEN

Methods based on molecular recognition mechanisms for the clean-up of veterinary drugs and their residues, such as immuno-, receptor- and acceptor-affinity and molecularly imprinted polymers (MIPs), have been described as selective tools to improve the selectivity and the reliability of analytical results. In this work, we tested the extraction recovery performances of a MISPE column, designed for multi-residual clean-up of beta-agonists. For this purpose, 18 different samples of calf urine were spiked at 0.25, 0.50 and 1.00 ppb with pooled standard solutions of clenbuterol (Clen), tulobuterol (Tolu), isoxsuprine (Isox), brombuterol (Brom), mapenterol (Mape) and ractopamine (Racto) and analysed on two independent analytical sessions, on a LC-MS/MS ion trap detector. Averaged recoveries, constant for each molecule considered, were 64.6% for Racto, 63.0% for Salm, 59.9% for Form, 54.7% for Brom, 52.0% for Clen, 41.8% for Mape, 38.6% for Tolu and 34.5% for Isox, respectively. Reproducibility studies gave a CV < 11% at the 0.25 ppb level. The decision limit for the identification of the target drugs ranged from 0.01 ppb for mapenterol to 0.19 ppb for salmeterol, when considering one precursor, and two product ions as identification points. Such findings indicate that the choice of the appropriate molecule as template in the MIP preparation is the critical factor to guarantee a reliable analytical multi-residue approach for beta-agonists, despite the structural differences among molecules exploiting almost the same pharmacological effect.


Asunto(s)
Agonistas Adrenérgicos beta/orina , Residuos de Medicamentos/análisis , Animales , Bovinos , Cromatografía Liquida/métodos , Espectrometría de Masas/métodos , Polímeros/química , Reproducibilidad de los Resultados
12.
Water Res ; 36(13): 3398-403, 2002 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12188140

RESUMEN

Plants can be an interesting tool for in situ remediation of drug contaminated waters. In a laboratory model Azolla filiculoides Lam., an aquatic fern known to absorb pollutants, has been exposed to an environmental persistent antibiotic commonly used in intensive farming, sulphadimethoxine (S), to test its bioremediation capability. In a 5 week experiment, plants were cultivated outdoor at four drug concentrations (50, 150, 300 and 450 mg l(-1)) in N-free mineral medium. Drug affects growth rate (as biomass yield per week), N2-fixation, heterocyst frequency, but plants are able to survive. Notwithstanding, at all concentrations tested drug was actively removed from the medium and the accumulation in the biomass is in order of magnitude up to mg g(-1) plant dry weight (1000 ppm). Drug uptake and degradation rates increase with S concentrations in the culture medium. The efficacy of the model was very high. These results demonstrated that Azolla can be taken into consideration as a tool for sulphonamides environmental monitoring and decontamination.


Asunto(s)
Antiinfecciosos/farmacocinética , Helechos , Sulfadimetoxina/farmacocinética , Purificación del Agua/métodos , Adsorción , Antiinfecciosos/análisis , Biodegradación Ambiental , Biomasa , Monitoreo del Ambiente , Helechos/crecimiento & desarrollo , Helechos/fisiología , Sulfadimetoxina/análisis
13.
Chemosphere ; 52(7): 1233-44, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12821004

RESUMEN

Phytotoxicity of enrofloxacin on crop plants Cucumis sativus, Lactuca sativa, Phaseolus vulgaris and Raphanus sativus was determined in a laboratory model: the effect of 50, 100 and 5000 microgl(-1) were evaluated after 30 days exposure by measuring post-germinative growth of primary root, hypocotyl, cotyledons and leaves. Concentrations between 50 and 5000 microgl(-1) induced both toxic effect and hormesis in plants, by significantly modifying both length of primary root, hypocotyl, cotyledons and the number/length of leaves. A toxic effect is induced by high concentration (5000 microgl(-1)), while hormesis occurs at low concentrations (50 and 100 microgl(-1)). A continuum between toxic effect and hormesis is found in the four plant species. Both toxic effect and hormesis can be related to an efficient plant drug uptake, in the order of microgg(-1). Plants are able to metabolize enrofloxacin into ciprofloxacin, as also happens in animals; Cucumis, Lactuca and Phaseolus biologically convert about one quarter of stored enrofloxacin. The ecological implication of enrofloxacin contamination in terrestrial environments is discussed.


Asunto(s)
Antiinfecciosos/toxicidad , Productos Agrícolas/efectos de los fármacos , Fluoroquinolonas , Quinolonas/toxicidad , Productos Agrícolas/crecimiento & desarrollo , Cucumis sativus/efectos de los fármacos , Cucumis sativus/crecimiento & desarrollo , Relación Dosis-Respuesta a Droga , Enrofloxacina , Lactuca/efectos de los fármacos , Lactuca/crecimiento & desarrollo , Phaseolus/efectos de los fármacos , Phaseolus/crecimiento & desarrollo , Estructuras de las Plantas/efectos de los fármacos , Estructuras de las Plantas/crecimiento & desarrollo , Raphanus/efectos de los fármacos , Raphanus/crecimiento & desarrollo
14.
J AOAC Int ; 86(1): 8-14, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12607734

RESUMEN

Adrenergic drugs for growth promotion have been outlawed in European meat production; however, molecules such as Ractopamine and Zilpaterol are licensed for feeding swine and cattle in the United States, Mexico, and South Africa. Analysis of bovine retinal extracts has recently shown considerable extension in the detection period following withdrawal. Previous studies demonstrated that residual concentrations of Clenbuterol and related substances in retinal tissue were > 100 ng/g at day 50 of withdrawal. A method was developed to identify and simultaneously quantify Clenbuterol-like substances with anilinic moieties and drugs with phenolic and catecholic moieties, such as Ractopamine and Zilpaterol, in retinal tissue. The method was validated according to SANCO/1805/2000. After extraction in 0.1 N HCl, samples were cleaned up on C18 non-endcapped solid-phase extraction columns and analyzed as trimethylchlorosilane derivatives by gas chromatography/tandem mass spectrometry, electron impact mode. At concentrations of agonists between 62.5 and 250.0 ng/g in bovine retina, mean recoveries ranged from 85.3 to 94.8%, repeatability was < 9.6%, and within-laboratory reproducibility was < 10.5%. The decision limits (CCalpha) were within the range of 66.3-70.4 ng/g, and the detection capability (CCbeta) varied from 73.9 to 79.8 ng/g. Results are discussed in terms of a multiresidue approach to improve reliability of the monitoring strategy.


Asunto(s)
Agonistas Adrenérgicos beta/análisis , Bovinos , Cromatografía de Gases y Espectrometría de Masas , Retina/química , Compuestos de Trimetilsililo/análisis , Animales , Clenbuterol/análisis , Residuos de Medicamentos/análisis , Fenetilaminas/análisis , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
J Chromatogr Sci ; 40(2): 92-6, 2002 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11881711

RESUMEN

More specific official methodology is needed to survey the illegal use of clenbuterol in animal production plus the synthesis of new compounds that currently elude routine analytical methods. The identification of a new adrenergic agonist, N1-(2-(4-amino-3,5-dichlorophenyl)-2-hydroxyethyl)-N1-isopropyl-propanamide (known as compound A) in animal feed has prompted studies to verify if the existing cleanup procedures developed for clenbuterol are really effective. This study considers the ion-exchange mechanism on cyanopropyl (CN), sulfonic cation exchange (SCX), mixed phase (MPH) (C8 + SCX), and nonendcapped C18 (C18NE) solid-phase extraction (SPE) columns. Results indicate that compound A (by contrast with clenbuterol) is not efficiently retained on the CN, SCX, and MPH SPE columns (recovery <10%). This finding thus leads to the development of a gas chromatography-tandem mass spectrometry procedure based on C18NE SPE that is able to purify both agonists from bovine livers spiked at 0.5, 1.0, and 2.0 ppb with a mean recovery of 93% for clenbuterol and 92% for compound A.


Asunto(s)
Agonistas Adrenérgicos/aislamiento & purificación , Cromatografía Líquida de Alta Presión/instrumentación , Clenbuterol/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Hígado/química , Animales , Bovinos , Reproducibilidad de los Resultados
16.
J Hazard Mater ; 215-216: 227-32, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22436341

RESUMEN

Oxytetracycline (OTC) is administered in high doses to livestocks and enters the environmental compartments as a consequence of animal waste disposal. As a first step in setting up a useful mycoremediation technique, an OTC lab degradation test was performed in liquid medium using the ligninolytic fungus Pleurotus ostreatus. OTC disappearance in culture medium was clearly evident as early as the third day of exposure onwards, with an almost complete removal after 14d. The drug removal was mediated by fungal absorption in the mycelia, where the OTC molecule underwent a degradation step, as demonstrated by mass spectrometry analyses. A putative degradation product, ADOTC (2-acetyl-2-decarboxamido-oxytetracycline) is proposed. Experimental conditions excluded OTC abiotic degradation; the degradation by extracellular laccase was also experimentally discarded.


Asunto(s)
Antibacterianos/metabolismo , Oxitetraciclina/metabolismo , Pleurotus/metabolismo , Biodegradación Ambiental , Lacasa/metabolismo , Micelio/metabolismo
17.
Dose Response ; 8(4): 414-27, 2010 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-21191482

RESUMEN

In order to evaluate the hormetic response of the weed Lythrum salicaria to drug exposure we investigated the effects of the antibiotic Sulfadimethoxine by growing Lythrum plants for 28 days on culture media containing different drug concentrations (between 0.005 and 50 mg.L(-1)). The antibiotic was absorbed by plants and can be found in plant tissue. The plant response was organ-dependent: roots, cotyledons and cotyledon petioles, were always affected by a toxic effect, whilst internodes and leaves length, showed a variable dose-depending response, with an increased growth at the lower drug concentrations and toxic effects at the higher ones. This variable response was probably dependant on different levels of local contamination resulting from a balance between accumulation rate and drug dilution in the increasing plant biomass. As a consequence, drug toxicity or hormetic response varied according to concentration and were different in each of the examined plant organ/tissue. Thus, even if hormesis can be considered a general plant response, each plant organ/tissue responds differently, depending on the local drug concentration and exposure time.

18.
J Chromatogr A ; 1217(17): 2832-9, 2010 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-20227702

RESUMEN

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 0.25-20.0 microg/kg. Confirmation of the nine NSAIDs is attained by fluorescence detection at characteristic excitation and emission wavelengths. The procedure described is simple and selective. Limits of quantification (LOQs) ranging between 0.25 and 20 microg/kg were measured; satisfactory trueness and within-laboratory reproducibility data were calculated at LOQ spiking levels, apart from 5-hydroxy-flunixin. The procedure developed is used in our laboratory for confirmation of each one of the above mentioned NSAIDs in bovine milk, to support results after HPLC quantitative analysis with UV-vis detection.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Cromatografía Líquida de Alta Presión/métodos , Residuos de Medicamentos/análisis , Leche/química , Animales , Bovinos , Cromatografía Líquida de Alta Presión/instrumentación , Contaminación de Alimentos/análisis , Límite de Detección , Espectrometría de Fluorescencia
19.
Rapid Commun Mass Spectrom ; 22(6): 841-54, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18278821

RESUMEN

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. For confirmatory purposes, two multi-residue reversed-phase ion trap liquid chromatography/electrospray ionisation tandem mass spectrometry (LC/ESI-MS/MS) methods were developed: the former to identify salicylic acid, naproxen, carprofen, flurbiprofen, ibuprofen, meclofenamic acid, niflumic acid, flunixin and its metabolite 5-hydroxyflunixin in the negative ion mode; the latter to identify ketoprofen, suxibutazone, diclofenac, mefenamic acid, tolfenamic acid, phenylbutazone and its metabolite oxyphenbutazone in the positive ion mode. These drugs are representative of different subclasses of NSAIDs not chemically related. The methods were in-house validated, evaluating specificity and calculating the mean recoveries, repeatability, within-laboratory reproducibility, and limits of quantification. For all the NSAIDs, apart from salicylic acid and 5-hydroxyflunixin, mean recoveries ranging between 69.0% and 96.7% were measured. The qualitative identification of all drugs was attained by their MS/MS spectra in the concentration range studied. Similarly, at 5 microg/kg all NSAIDs, apart from flurbiprofen, were unambiguously confirmed.


Asunto(s)
Antiinflamatorios no Esteroideos/análisis , Antiinflamatorios no Esteroideos/química , Cromatografía Líquida de Alta Presión/métodos , Análisis de los Alimentos/métodos , Contaminación de Alimentos/análisis , Leche/química , Espectrometría de Masa por Ionización de Electrospray/métodos , Animales , Bovinos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
20.
Anal Chim Acta ; 587(1): 67-74, 2007 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-17386755

RESUMEN

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. In this paper, we describe different strategies for purifying some beta(2)-agonist drugs of new concept, more hydrophobic than clenbuterol. A two-step clean up procedure, prior to gas chromatography-mass spectrometry analysis, was developed for the multi-residue determination of these beta(2)-agonists from bovine hair and urine. The purification strategy we chose was based on adsorption solid phase extraction and, subsequently, on specific molecular recognition by affinity chromatography. The affinity columns were homemade by coupling bovine alpha(1)-acid glycoprotein, a plasmatic acceptor for basic drugs, to a chromatographic support; their effectiveness for purifying new beta(2)-agonists was discussed. The data about method recoveries and repeatability were also reported.


Asunto(s)
Agonistas Adrenérgicos beta/aislamiento & purificación , Clenbuterol/análogos & derivados , Clenbuterol/aislamiento & purificación , Cromatografía de Gases y Espectrometría de Masas/métodos , Detección de Abuso de Sustancias/métodos , Agonistas Adrenérgicos beta/farmacología , Animales , Bovinos , Cromatografía/métodos , Cromatografía de Afinidad/métodos , Cromatografía Líquida de Alta Presión/métodos , Clenbuterol/farmacología , Cabello/metabolismo , Indicadores y Reactivos/farmacología , Orosomucoide/química , Sensibilidad y Especificidad , Extracción en Fase Sólida/métodos , Orina/química
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