RESUMO
Tagetes patula L. (Asteraceae), popularmente conhecida como cravo de defunto ou cravo francês, é utilizada na medicina popular como antisséptica, depurativa do sangue e repelente de insetos. O presente estudo avaliou a atividade antisséptica de sabonete líquido contendo extrato glicólico de T. patula 7,5% (p/v). O extrato glicólico foi obtido por turbo-extração utilizando propilenoglicol e etanol (7:3; v/v) a 10 % (p/v). A avaliação fitoquímica preliminar da droga vegetal indicou a presença de compostos fenólicos e teor de flavonoides de 5,73% ± 0,19 (CV = 3,33%). No teste para avaliação da atividade antimicrobiana houve a inibição do crescimento de Staphylococcus aureus na concentração de avaliada.
Tagetes patula L. (Asteraceae), or French marigold, known in Brazil as cravo-de-defunto, is used in folk medicine as antiseptic, blood thinner and insect repellent. Current study analyzes the antiseptic activity of the liquid soap with the glycolic extract of T.patula 7.5% (p/v). Glycolic extract was obtained by turbo-extraction with propylenoglycol and ethanol (7:3; v/v) 10 % (p/v). Preliminary photochemical evaluation of the vegetal drug showed phenolic compounds and flavonoid rates at 5.73% ± 0.19 (CV = 3.33%). When the pharmaceutical formulation was evaluated for antimicrobial activity, growth inhibition of Staphylococcus aureus occurred at the assessed concentration.
Assuntos
Flavonoides , Anti-Infecciosos Locais , Preparações Farmacêuticas , Compostos Fenólicos , Compostos FitoquímicosRESUMO
In the present study, the performance of multi-walled carbon nanotubes (MWCNTs) grafted with 3-mercaptopropyltrimethoxysilane (3-MPTMS), used as a solid phase extractor for Cd(2+) preconcentration in a flow injection system coupled to flame atomic absorption spectrometry (FAAS), was evaluated. The procedure involved the preconcentration of 20.0 mL of Cd(2+) solution at pH 7.5 (0.1 mol L(-1) buffer phosphate) through 70 mg of 3-MPTMS-grafted MWCNTs packed into a minicolumn at 6.0 mL min(-1). The elution step was carried out with 1.0 mol L(-1) HCl. Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were used to estimate the extent of the MWCNT chemical modification. The 3-MPTMS-grafted MWCNTs provided a 1.68 times improvement in the sensitivity of the Cd(2+) FAAS determination compared to the unsilanized oxidized MWCNTs. The following parameters were obtained: preconcentration factor of 31.5, consumptive index of 0.635 mL, sample throughput of 14 h(-1), and concentration efficiency of 9.46 min(-1). The analytical curve was constructed in the range of 1.0-60.0 µg L(-1) (r=0.9988), and the detection and quantification limits were found to be 0.15 µg L(-1) and 0.62 µg L(-1), respectively. Different types of water samples and cigarette sample were successfully analyzed, and the results were compared using electrothermal atomic absorption spectrometry (ETAAS) as reference technique. In addition, the accuracy of proposed method was also checked by analysis of certified reference material NIST SRM 1573a (tomato leaves) and standard reference material NIST SRM 1643e (trace elements in natural waters).
Assuntos
Cádmio/isolamento & purificação , Nanotubos de Carbono/química , Silanos/química , Poluentes Químicos da Água/isolamento & purificação , Acetatos , Algoritmos , Soluções Tampão , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Solanum lycopersicum/química , Microscopia Eletrônica de Varredura , Sistemas On-Line , Compostos de Organossilício , Fosfatos , Espectrofotometria Atômica , Propriedades de Superfície , Nicotiana/químicaRESUMO
The present paper describes the synthesis of a new chemically modified cellulose microfiber through oxidation with sodium periodate and functionalization with N,N'-bis (2-aminoethyl)-1,2-ethanediamine for the fast and selective preconcentration of Cd(II) ions in flow system analysis. The new sorbent was characterized by FTIR, SEM, and surface area values. The uptake behavior of Cd(II) ions onto this sorbent was evaluated from kinetic data, pseudo-first-order and pseudo-second-order models, as well as from Langmuir, Freundlich and Langmuir-Freundlich adsorption isotherms. The maximum sorption capacity of 4.59 mg g(-1) was estimated by the Langmuir-Freundlich model with fast kinetics for the sorption of Cd(II) described by the pseudo-second-order kinetic model. After characterization, the sorbent was packed in a mini-column, and a fast flow injection preconcentration system for Cd(II) determination by FAAS was developed. The best Cd(II) preconcentration condition, obtained by means of factorial design and response surface methodology, was achieved at pH 9.36 and a flow rate of 10 mL min(-1) followed by elution with 1.0 mol L(-1) nitric acid. By using 78 s preconcentration time, fast and highly sensitive determination of Cd(II) ions could be achieved with a limit of quantification of 0.20 µg L(-1), preconcentration factor of 26, consumption index of 0.5 mL, concentration efficiency of 20 min(-1), and sample throughput of 39 h(-1). The repeatability for 10 replicate determinations was found to be 7.8 and 2.5% for Cd(II) ion concentrations of 5.0 and 100.0 µg L(-1), respectively. The new sorbent efficiency for the interference-free preconcentration of Cd(II) ions was assessed by analysis of tap, mineral and lake waters, as well as synthetic seawater and normal saline waters. Furthermore, complex samples, such as biological samples, could be analysed by the proposed method in accordance with the accuracy attested by analysis of certified reference materials, TORT-2 (lobster hepatopancreas), and DOLT-4 (dogfish liver).