Comparação entre métodos de quantificação em cromatografia gasosa: um experimento para cursos de química

Bastos, Carolina; Parrilha, Gabrieli L.; Filho, Milton Baptista; Canela, Maria Cristina

doi:10.1590/s0100-40422009000500043

Cited by 11 publications

(5 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Phellandrene, linalool, caryophylene and nerolidol (Sigma-Aldrich) were selected to represent the response factors for monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons and oxygenated sesquiterpenes, respectively. Analyses for the RRF calculation were completed five times at four concentrations (0.0104, 0.0146, 0.0187 and 0.0229 mg·mL −1 ) [ 62 ] and the average response factors were obtained.…”

Section: Methodsmentioning

confidence: 99%

Chemical Composition and Bioactivity of Essential Oil from Blepharocalyx salicifolius

Furtado

Borges

Teixeira

et al. 2018

IJMS

View full text Add to dashboard Cite

Natural products represent a source of biologically active molecules that have an important role in drug discovery. The aromatic plant Blepharocalyx salicifolius has a diverse chemical constitution but the biological activities of its essential oils have not been thoroughly investigated. The aims of this paper were to evaluate in vitro cytotoxic, antifungal and antibacterial activities of an essential oil from leaves of B. salicifolius and to identify its main chemical constituents. The essential oil was extracted by steam distillation, chemical composition was determined by gas chromatography/mass spectrometry, and biological activities were performed by a microdilution broth method. The yield of essential oil was 0.86% (w/w), and the main constituents identified were bicyclogermacrene (17.50%), globulol (14.13%), viridiflorol (8.83%), γ-eudesmol (7.89%) and α-eudesmol (6.88%). The essential oil was cytotoxic against the MDA-MB-231 (46.60 μg·mL−1) breast cancer cell line, being more selective for this cell type compared to the normal breast cell line MCF-10A (314.44 μg·mL−1). Flow cytometry and cytotoxicity results showed that this oil does not act by inducing cell death, but rather by impairment of cellular metabolism specifically of the cancer cells. Furthermore, it presented antifungal activity against Paracoccidioides brasiliensis (156.25 μg·mL−1) but was inactive against other fungi and bacteria. Essential oil from B. salicifolius showed promising biological activities and is therefore a source of molecules to be exploited in medicine or by the pharmaceutical industry.

show abstract

Section: Methodsmentioning

confidence: 99%

Chemical Composition and Bioactivity of Essential Oil from Blepharocalyx salicifolius

Furtado

Borges

Teixeira

et al. 2018

IJMS

View full text Add to dashboard Cite

show abstract

“…Otherwise, the parameter is considered insignificant and should be removed from the linear equation (y = a + bx). 27 The LODs and LOQs were estimated from successive injection of dilute solutions of the lowest concentration that resulted in signal/noise ratios of three and ten, respectively. Accuracy was demonstrated by the recovery experiments through analyzing samples spiked with pesticides at 0.08, 0.1, 0.14, 0.17, 0.35 and 1.17 mg kg -1 , performed by triplicate assay and duplicate injection.…”

Section: Methods Validationmentioning

confidence: 99%

“…This proposed method showed good linearity, expressed by the values of R near 1.00, with the lowest value being 0.993 (ethoprophos curves in the matrix), and all of the analytes were in accordance with the guidelines of ANVISA 25 that recommend values above 0.99. However, ideally the regression line should pass through the origin, 27,35 but this fact is rarely observed. Therefore, the adjustment of the analytical curve by statistical tests to minimize quantitative errors must be taken into account.…”

Section: Matrix Effect and Linearitymentioning

confidence: 99%

Organophosphorus Pesticide in Sapodilla (Manilkara zapota) Fruit

Alcântara

Paz

Rodrigues

et al. 2018

J. Braz. Chem. Soc.

View full text Add to dashboard Cite

A method based on QuEChERS (quick, easy, cheap, effective, rugged, and safe) extraction and gas chromatography-mass spectrometry (GC-MS) detection was described for the pesticides dichlorvos, disulfoton, ethoprophos, parathion methyl, fenchlorphos, chlorpyrifos, azinphos methyl and prothiofos in sapodilla. For all compounds studies, it was observed a strong matrix effect showing the need to use matrix matched calibration strategy. Method was validated, and good linearity (R > 0.99) was obtained for all pesticides studied with limits of detection (LODs) and quantification (LOQs) ranging from 0.01 to 0.06 mg kg -1 and 0.03 to 0.2 mg kg -1 , respectively. Recovery studies were performed at different levels (0.08, 0.10, 0.14, 0.20, 0.35 and 1.17 mg kg -1 ) and showed good results (between 70 and 120% with relative standard deviation (RSD) < 20%). A statistical test was applied to the coefficients of the analytical curves obtained in the sapodilla matrix. Analyses of commercial samples showed chlorpyrifos were detected in about 70 and 33% for fruit and pulps samples, respectively. It should be noted that chlorpyrifos is not permitted in sapodilla crops by ANVISA and EC guidelines.

show abstract

“…A técnica de cromatografia gasosa envolve um detector capaz de responder a determinado composto de maneira proporcional a sua concentração no ambiente, realiza análises qualitativas e quantitativas de forma rápida na determinação de compostos presentes em concentrações relativamente baixas em diferentes amostragens, o método direto envolve a preparação de uma série de soluções padrão com concentração próxima ao composto a ser analisado (LIGIERO et al, 2009). Essa técnica é utilizada para determinar tanto a concentração de amônia nos ambientes quanto a concentração de amônia capturada nos coletores, bem como para determinar a concentração de hexafluoreto de enxofre (SF 6 ), quando esse é utilizado como gás marcador para determinar a taxa de emissão de amônia de forma indireta (SARAZ et al, 2013).…”

Section: Cromatografia Gasosaunclassified

Quantificação De Amônia Em Instalações De Produção De Frangos De Corte Em Clima Quente

et al. 2018

View full text Add to dashboard Cite

A qualidade do ar é um dos fatores mais importantes na produção avícola, uma vez que os poluentes aéreos podem alterar as características ideais do ar, favorecendo a susceptibilidade a doenças, além de causar prejuízos na produção. Apesar da grande diversidade de métodos existentes para quantificar a amônia, nem sempre eles podem ser aplicados nas instalações dos países de climas quentes. Assim, ainda são necessários estudos de comparação, adaptação e aplicação de métodos utilizados para quantificar a amônia. Com isso objetivou-se com essa revisão apresentar os métodos mais comumente utilizados para determinar a concentração e a emissão de amônia em instalações de produção animal em todo o mundo e ao mesmo tempo avaliar a sua aplicação nos aviários abertos utilizados nos países de climas quentes. A escolha do método mais adequado deve ser baseada considerando-se os fatores relevantes para a determinação da amônia. Diante da maior dificuldade na determinação da taxa de ventilação nos aviários abertos, as metodologias para avaliação da emissão de amônia que não dependam desse parâmetro são as mais indicadas.

show abstract

Comparação entre métodos de quantificação em cromatografia gasosa: um experimento para cursos de química

Cited by 11 publications

References 3 publications

Chemical Composition and Bioactivity of Essential Oil from Blepharocalyx salicifolius

Chemical Composition and Bioactivity of Essential Oil from Blepharocalyx salicifolius

Organophosphorus Pesticide in Sapodilla (Manilkara zapota) Fruit

Quantificação De Amônia Em Instalações De Produção De Frangos De Corte Em Clima Quente

Contact Info

Product

Resources

About