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Simultaneous GC-NCI-MS Determination of Persistent Organic Pollutants and Curre...
Viera,Mariela S.; Ferronato,Giovana; Abreu,Herliana D. F.; Prestes,Osmar D.; Adaime,Martha B.; Zanella,RenatoTo preserve human health, persistent organic pollutants (POPs) and current-use pesticides (CUPs) should be monitored in fatty tissues, including breast milk. Therefore, this study aimed to optimize sample preparation conditions using a 32 factorial design for the determination of POPs and CUPs by gas chromatography coupled to mass spectrometry with negative chemical ionization (GC-NCI-MS). The method was valida...
Experimental reproduction of congenital anomalies in the progeny of cows fed ap...
Wicpolt,Nathalia S.; Morais,Raissa M.; Molossi,Francieli Adriane; Ogliari,Daiane; Mezzalira,Joana; Prestes,Osmar D.; Zanella,Renato; Gava,AldoABSTRACT: This study aimed to describe and discuss the results of an experiment carried out in two stages with pregnant cows fed 25kg/apple pomace/day. The first stage involved 16 pregnant Holstein Friesian cows divided into four groups: Group 0 - Control (5 cows); Group I - 1 month-gestation (4 cows); Group II - 3 month-gestation (4 cows); Group III - 6 month-gestation (3 cows) and was performed from September...
Determination of Six Synthetic Dyes in Sports Drinks by Dispersive Solid-Phase ...
Floriano,Luana; Ribeiro,Lucila C.; Saibt,Nathália; Bandeira,Nelson M. G.; Prestes,Osmar D.; Zanella,RenatoA simple, fast and efficient method was developed for determination of six synthetic dyes (Tartrazine, Sunset Yellow, Amaranth, Ponceau 4R, Indigo Carmine and Brilliant Blue) in sports drinks using dispersive solid-phase extraction (d-SPE) with the polymeric sorbent Oasis® HLB. Sample preparation using d-SPE permitted to simplify the procedure and use less sorbent in comparison with SPE. The use of a syringe fo...
Fast Sample Preparation Method Using Ultra-High Performance Liquid Chromatograp...
Bernardi,Gabrieli; Rizzetti,Tiele M.; Adaime,Martha B.; Zanella,Renato; Prestes,Osmar D.An easy and efficient sample preparation method was developed for the determination of natamycin residues in wine samples by solvent extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) analysis. After choosing acetonitrile as extraction solvent, an experimental design was carried out with different amounts of C18 and primary secondary amine (PSA) sorbent...
Evaluation of QuEChERS Sample Preparation for Determination of Avermectins Resi...
Bandeira,Nelson M. G.; Ribeiro,Lucila C.; Rizzetti,Tiele M.; Martins,Manoel L.; Adaime,Martha B.; Zanella,Renato; Prestes,Osmar D.A fast and sensitive method using high performance liquid chromatography-fluorescence detection (HPLC-FD) and ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was developed and validated for the determination of avermectins residues in ovine muscle samples. QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation based on acetonitrile extraction followed by...
Evaluation of QuEChERS Sample Preparation and Gas Chromatography Coupled to Mas...
Volpatto,Fernanda; Wastowski,Arci D.; Bernardi,Gabrieli; Prestes,Osmar D.; Zanella,Renato; Adaime,Martha B.An effective analytical method for pesticides multiresidue determination in grape samples was developed and validated. A modified quick, easy, cheap, effective, robust and safe (QuEChERS) method was used to extract the target compounds. Several sorbent materials were tested for the clean-up step using dispersive solid phase extraction (d-SPE) and Florisil® was selected. Samples extracts were evaporated before i...
Steroidogenic enzymes mRNA expression profile and steroids production in bovine...
Rigo,Melânia Lazzari; Dau,Andressa Minussi Pereira; Glanzner,Werner Giehl; Martins,Manoel; Zanella,Renato; Rizzetti,Tiele MedianeiraThe main objective of this study was to detect the steroidogenic effects of Ang II in bovine theca cells in vitro. Bovine theca cells were obtained from follicles (larger than 10mm of diameter) collected from a local abattoir and submitted to different treatments in a sequence of experiments. In experiment 1, CYP17A1 mRNA profile was evaluated in LH- (10ng ml-1) and Ang II-treated (0.1µM) theca cells. In experi...
Spatial and temporal biomarkers responses of Astyanax jacuhiensis (Cope, 1894)(...
Loro,Vania Lucia; Murussi,Camila; Menezes,Charlene; Leitemperger,Jossiele; Severo,Eduardo; Guerra,Luciana; Costa,Maiara; Perazzo,Giselle XavierDue to intense agricultural activity in the rio Uruguai (South Brazil), there is the potential for aquatic contamination by agrochemicals. In this region, there are many reservoirs to meet the water demand for rice fields, forming lentic environments. In line with this information, the aim of this study was to show a comparative analysis of some biomarkers, such as lipid peroxidation (TBARS), gluthatione S-tran...
Development of a Multiresidue Method for Pesticide Analysis in Drinking Water b...
Donato,Filipe F.; Martins,Manoel L.; Munaretto,Juliana S.; Prestes,Osmar D.; Adaime,Martha B.; Zanella,RenatoIn this work, a method for multiclass determination of 70 pesticides residues with different properties in drinking water using solid phase extraction (SPE) with polymeric sorbent and determination by gas and liquid chromatography coupled to tandem mass spectrometry (GC-MS/MS and LC-MS/MS) was developed and validated. Different sample volumes, sorbents and elution solvents were evaluated. The best results were ...
Zooplankton community responses to the mixture of imazethapyr with imazapic and...
Reimche,Geovane Boschmann; Machado,Sérgio Luiz de Oliveira; Zanella,Renato; Vicari,Michele Câmara de; Piccinini,Fernando; Golombieski,Jaqueline IneuThe aim of this study was to assess the effect of concentrations of imazethapyr, imazapic, and bispyribac-sodium herbicides on zooplankton community (Cladocer, Copepod and Rotifer) in rice paddy fields. The decrease of half-life dissipation (DT50) of the herbicides under study in water was: imazethapyr, imazapic, and bispyribac-sodium with an average of 3.75, 3.73 and 1.91 days, respectively. The mixture of ima...