Simultaneous Determination
Mostrando 1-12 de 448 artigos, teses e dissertações.
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1. Simultaneous GC-NCI-MS Determination of Persistent Organic Pollutants and Current-Use Pesticides in Breast Milk Samples
To 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
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Thermal Infrared Enthalpimetry Method for the Determination of Hypochlorite in Bleaching Solutions
Thermal infrared enthalpimetry (TIE) was used for hypochlorite determination in commercial hypochlorite-based bleaching solutions. Experimental parameters were evaluated for the reaction with a hydrogen peroxide solution. The most relevant conditions were 5% H2O2 (m/m) solution, stirring speed of 250 rpm, dispensing rate of 0.57 mL s-1, and 10 s after reacti
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. Preparation of Silicon Oxycarbide (SiCO) Ceramics from Different Polymer Architectures and Assessment on the Performance as Electrodic Materials for Voltammetric Sensing of Antioxidant Phenolic Compounds
Silicon oxycarbide (SiCO) ceramics obtained from polymer pyrolysis and with varied carbon contents were prepared and evaluated as new electrodic materials for sensing of tert butylhydroquinone (TBHQ) and butylated hydroxyanisole (BHA) antioxidants. Three polymers were synthesized varying molecular architecture and aromatic carbon groups, followed by pyrolysi
Journal of the Brazilian Chemical Society. Publicado em: 2022
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4. Validation and Application of a Methodology for Quantifying Levels of Parabens in Sports Supplements from Brazil Using Liquid Chromatography-Mass Spectrometry
Although parabens have been reported to be used as antimicrobial preservatives in personal care products, pharmaceuticals, and foodstuffs, little is known about the occurrence of these compounds in sports supplements. In this study, a simple, fast and sensitive liquid chromatography tandem mass spectrometry method for simultaneous determination of five commo
Journal of the Brazilian Chemical Society. Publicado em: 2022
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5. Development of a Simple and Fast Procedure Based on Acid Dilution for Determination of Macro and Microelements in Guarana-Based Beverages by ICP OES
A simple analytical procedure is proposed for the direct analysis of guarana-based beverages in order to determine nutrient elements by inductively coupled plasma optical emission spectrometry (ICP OES). A Box-Behnken design, combined with Derringer’s desirability function, was applied to the simultaneous optimization of the ICP OES radiofrequency (RF), sa
J. Braz. Chem. Soc.. Publicado em: 2021-07
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6. A Gas Chromatography Method for Simultaneous Quantification of Inorganic Gases and Light Hydrocarbons Generated in Thermochemical Processes
This paper reports a method for simultaneous determination of H2, O2, N2, CO, CO2, CH4, C2H2, C2H4, C2H6, C3H4 (propadiene and propyne), C3H6, C3H8 and C4H10 (n-butane and isobutane) by gas chromatography using thermal conductivity and flame ionization detectors. A single porous layer open tubular column (0.53 mm internal diameter ? 30 m length ? 30 µm thic
J. Braz. Chem. Soc.. Publicado em: 2021-06
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7. Reduced Graphene Oxide-Cadmium Sulfide Quantum Dots Nanocomposite Based Dispersive Solid Phase Microextraction for Ultra-Trace Determination of Carbamazepine and Phenobarbital
This research presents a fast, sensitive, and selective ultrasound-assisted dispersive solid phase microextraction technique for simultaneous preconcentration and determination of ultra-trace amount of carbamazepine and phenobarbital. Reduced graphene oxide sheets decorated with cadmium sulfide quantum dots was synthesized, characterized, and used as a high
J. Braz. Chem. Soc.. Publicado em: 2021-04
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8. Development and Validation of a Gas Chromatographic Method for the Quantification of Minor Alkaloids in Cocaine
The quantification of minor alkaloids in seized cocaine can provide information for drug profiling and law enforcement initiatives. This work presents the development and validation of an analytical method to quantitate minor alkaloids in cocaine samples using gas chromatography with flame ionization detector, after derivatization. The method was validated i
J. Braz. Chem. Soc.. Publicado em: 2021-04
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9. Novo Qualis: rumos e rumores
Pharmaceutical cocrystals are composed of a drug and a coformer and are currently gaining attention due to their possibility of improving drug solubility. Quantitative determination of cocrystals is usually carried out by liquid chromatography method, but an alternative for the same is derivative UV spectrophotometry. Cocrystals of lamotrigine (LAM) were for
Rev. Bras. Hist.. Publicado em: 2020-12
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10. Development of a First-Order Derivative UV Spectrophotometric Method for the Assay and Solubility Evaluation of Lamotrigine and Nicotinamide Cocrystals
Pharmaceutical cocrystals are composed of a drug and a coformer and are currently gaining attention due to their possibility of improving drug solubility. Quantitative determination of cocrystals is usually carried out by liquid chromatography method, but an alternative for the same is derivative UV spectrophotometry. Cocrystals of lamotrigine (LAM) were for
J. Braz. Chem. Soc.. Publicado em: 2020-12
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11. Synergistic Supramolecular Effect on the Electro-Oxidation of Biological Relevant Molecules: A Novel Sensor for Simultaneous Determination of Epinephrine and Uric Acid in Human Urine Using MWCNT and a Copper(II) Complex
In this paper a novel supramolecular strategy to improve the efficiency of a voltammetric sensor to determine two biologically relevant molecules (epinephrine (EP) and uric acid (UA)) is presented. The strategy is based on the use of a glassy carbon electrode modified with a copper(II) complex ([Cu(H2dimpy)Cl]PF6) adsorbed on multi-walled carbon nanotubes (M
J. Braz. Chem. Soc.. Publicado em: 2020-11
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12. Tópicos Emergentes em Insuficiência Cardíaca: Terapias Intervencionistas na Insuficiência Cardíaca
In this paper a novel supramolecular strategy to improve the efficiency of a voltammetric sensor to determine two biologically relevant molecules (epinephrine (EP) and uric acid (UA)) is presented. The strategy is based on the use of a glassy carbon electrode modified with a copper(II) complex ([Cu(H2dimpy)Cl]PF6) adsorbed on multi-walled carbon nanotubes (M
Arq. Bras. Cardiol.. Publicado em: 2020-11