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1.
J Chromatogr A ; 1719: 464753, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38394784

RESUMO

In this study, MIL-88(Fe) coordinated to carboxymethyl cellulose fibers was successfully synthesized, characterized, and utilized as a nanocomposite for the dispersive solid phase microextraction of butachlor and acetochlor. These analytes served as representative analytes for acetanilide herbicides (AHs) present in real samples. Effective parameters on the extraction efficiency were investigated to maximize the analytical performance of the developed method. Under optimized conditions, which encompassed sorbent amount of 12 mg, solution pH of 7.0, 4.0 min of the vortex time, 3.0 min of the extraction time, chloroform as desorption agent and no salt addition, the developed method exhibited remarkable figures of merit, such as high linearity (R2> 0.99), low limits of detection of 0.90 ng mL-1, substantial preconcentration factors (between 213 and 228), relative recoveries in the range of 90.8% to 109%, and good repeatability with relative standard deviations equal or below 7.2%. After validation, the developed method was applied to detect AHs in various cereal and agricultural soil samples.


Assuntos
Herbicidas , Microextração em Fase Líquida , Nanocompostos , Microextração em Fase Sólida/métodos , Herbicidas/análise , Carboximetilcelulose Sódica , Grão Comestível/química , Solo , Acetanilidas/química , Extração em Fase Sólida/métodos , Microextração em Fase Líquida/métodos
2.
Mikrochim Acta ; 191(2): 98, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38227067

RESUMO

Fe3O4@nitrogen-doped carbon core-double shell nanotubes (Fe3O4@N-C C-DSNTs) were successfully synthesized and applied as a novel nanosorbent in ultrasonic assisted dispersive magnetic solid phase extraction (UA-DMSPE) of tribenuron-methyl, fenpyroximate, and iprodione. Subsequently, corona discharge ion mobility spectrometry (CD-IMS) was employed for the detection of the extracted analytes. Effective parameters on the extraction recovery percentage (ER%) were systematically investigated and optimized. Under optimal conditions, UA-DMSPE-CD-IMS demonstrated remarkable linearity in different ranges within 1.0 - 700 ng mL-1 with correlation coefficients exceeding 0.993, repeatability values below 6.9%, limits of detection ranging from 0.30 to 0.90 ng mL-1, high preconcentration factors (418 - 435), and ER% values (83 - 87%). The potential of the proposed method was further demonstrated by effectively determining the targeted pesticides in various environmental soil and water samples, exhibiting relative recoveries in the range 92.1 - 102%.

3.
J Chromatogr A ; 1462: 27-34, 2016 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-27495366

RESUMO

In this research, a sample preparation method termed solvent-assisted dispersive solid-phase extraction (SA-DSPE) was applied. The used sample preparation method was based on the dispersion of the sorbent into the aqueous sample to maximize the interaction surface. In this approach, the dispersion of the sorbent at a very low milligram level was received by inserting a solution of the sorbent and disperser solvent into the aqueous sample. The cloudy solution created from the dispersion of the sorbent in the bulk aqueous sample. After pre-concentration of the diazinon, the cloudy solution was centrifuged and diazinon in the sediment phase dissolved in ethanol and determined by gas chromatography-flame ionization detector. Under the optimized conditions (pH of solution=7.0, Sorbent: benzophenone, 2%, Disperser solvent: ethanol, 500µL, Centrifuge: centrifuged at 4000rpm for 3min), the method detection limit for diazinon was 0.2, 0.3, 0.3 and 0.3µgL(-1) for distilled water, lake water, waste water and urine sample, respectively. Furthermore, the pre-concentration factor was 363.8, 356.1, 360.7 and 353.38 in distilled water, waste water, lake water and urine sample, respectively. SA-DSPE was successfully used for trace monitoring of diazinon in urine, lake and waste water samples.


Assuntos
Diazinon/análise , Diazinon/urina , Extração em Fase Sólida/métodos , Solventes/química , Poluentes Químicos da Água/análise , Água/química , Benzofenonas/química , Ionização de Chama , Humanos , Lagos/química , Limite de Detecção , Águas Residuárias/química
4.
J Sep Sci ; 39(19): 3798-3805, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27514993

RESUMO

In this work, an efficient sample preparation method termed solvent-assisted dispersive solid-phase extraction was applied. The used sample preparation method was based on the dispersion of the sorbent (benzophenone) into the aqueous sample to maximize the interaction surface. In this approach, the dispersion of the sorbent at a very low milligram level was achieved by inserting a solution of the sorbent and disperser solvent into the aqueous sample. The cloudy solution created from the dispersion of the sorbent in the bulk aqueous sample. After pre-concentration of the butachlor, the cloudy solution was centrifuged and butachlor in the sediment phase dissolved in ethanol and determined by gas chromatography with flame ionization detection. Under the optimized conditions (solution pH = 7.0, sorbent: benzophenone, 2%, disperser solvent: ethanol, 500 µL, centrifuged at 4000 rpm for 3 min), the method detection limit for butachlor was 2, 3 and 3 µg/L for distilled water, waste water, and urine sample, respectively. Furthermore, the preconcentration factor was 198.8, 175.0, and 174.2 in distilled water, waste water, and urine sample, respectively. Solvent-assisted dispersive solid-phase extraction was successfully used for the trace monitoring of butachlor in urine and waste water samples.


Assuntos
Acetanilidas/análise , Acetanilidas/isolamento & purificação , Extração em Fase Sólida/métodos , Águas Residuárias/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Cromatografia Gasosa , Limite de Detecção , Extração em Fase Sólida/instrumentação
5.
Z Naturforsch C J Biosci ; 59(11-12): 777-81, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15666533

RESUMO

The antimicrobial activity, essential oil composition and micromorphology of trichomes of Satureja laxiflora C. Koch, a native plant from Iran, were studied. The essential oil was obtained from the aerial parts at the flowering stage by hydrodistillation, and analyzed by GC and GC/MS. Thirty-three compounds representing 99.1% of the total oil were characterized. The major compounds were thymol (63.9%) and gamma-terpinene (11.9%) followed by carvacrol (4.8%), p-cymene (3.9%), geraniol (3.2%) and geranyl acetate (3.1%). Furthermore, the essential oil and its three main components were tested against two bacteria and three fungi. The result of the bioassays has been shown that the oil possesses potent antimicrobial property. Chemical studies confirmed that a major portion of this antimicrobial activity is due to thymol present in the oil. Micromorphological analysis by SEM of both vegetative and reproductive organs revealed the presence of abundant sessile capitate and sparse short-stalked glandular trichomes along with retrorse eglandular hairs, giving useful diagnostic characters for identification of this medicinal plant.


Assuntos
Anti-Infecciosos/isolamento & purificação , Óleos Voláteis/química , Satureja/química , Anti-Infecciosos/farmacologia , Aspergillus niger/efeitos dos fármacos , Bactérias/efeitos dos fármacos , Cromatografia Gasosa , Flores/química , Flores/ultraestrutura , Cromatografia Gasosa-Espectrometria de Massas , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Componentes Aéreos da Planta/química , Folhas de Planta/química , Folhas de Planta/ultraestrutura , Caules de Planta/química , Caules de Planta/ultraestrutura , Saccharomyces cerevisiae/efeitos dos fármacos
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