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1.
J Chromatogr A ; 1719: 464753, 2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38394784

RESUMEN

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.


Asunto(s)
Herbicidas , Microextracción en Fase Líquida , Nanocompuestos , Microextracción en Fase Sólida/métodos , Herbicidas/análisis , Carboximetilcelulosa de Sodio , Grano Comestible/química , Suelo , Acetanilidas/química , Extracción en Fase Sólida/métodos , Microextracción en Fase Líquida/métodos
2.
Mikrochim Acta ; 191(2): 98, 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38227067

RESUMEN

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.
Mikrochim Acta ; 190(10): 377, 2023 09 04.
Artículo en Inglés | MEDLINE | ID: mdl-37661209

RESUMEN

A polybenzidine-modified Fe3O4@SiO2 nanocomposite was successfully synthesized through a chemical oxidation method and employed as a novel sorbent in dispersive magnetic solid phase extraction (DMSPE) for the preconcentration and determination of three triazole fungicides (TFs), namely diniconazole, tebuconazole, and triticonazole in river water, rice paddy soil, and grape samples. The synthesis method involved a polybenzidine self-assembly coating on Fe3O4@SiO2 magnetic composite. Characterization techniques such as FT-IR, XRD, FESEM, EDX, and VSM were used to confirm the correctness of the synthesized nano-sorbent. The target TFs were determined in actual samples using the synthesized nanocomposite sorbent in combination with gas chromatography-flame ionization detection (FID). Several variables were carefully optimized , including the sample pH, sorbent dosage, extraction time, ionic strength, and desorption condition (solvent type, volume, and time). Under the optimized experimental conditions, the method exhibited linearity in the concentration range 5-1000 ng mL-1 for triticonazole and 2-1000 ng mL-1 for diniconazole and tebuconazole. The limits of detection (LOD) for the three TFs were in the range 0.6-1.5 ng mL-1. The method demonstrated acceptable precision with intra-day and inter-day relative standard deviation (RSD) values of less than 6.5%. The enrichment factors ranged from 248 to 254. Finally, the method applicability was evaluated by determining TFs in river water, rice paddy soil, and grape samples with recoveries in the range 90.5-106, indicating that the matrix effect was negligible in the proposed DMSPE procedure.


Asunto(s)
Fungicidas Industriales , Nanopartículas de Magnetita , Oryza , Dióxido de Silicio , Espectroscopía Infrarroja por Transformada de Fourier , Suelo , Extracción en Fase Sólida , Fenómenos Magnéticos , Agua
4.
Food Chem ; 403: 134273, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36174345

RESUMEN

Herein, an ultrasound-assisted dispersive solid phase microextraction (UA-DSPME) approach has been described for trace level analysis of triazole fungicides in real samples. For this purpose, a new nanosorbent was prepared through modification of carboxymethylcellulose biopolymer with zinc-based metal-organic framework and graphene oxide, and fully characterized. Then, the effect of extraction parameters on extraction efficiency was optimized for the microextraction process. Finally, desorbed triazole fungicides with ethanol were determined using gas chromatography equipped with flame ionization detector. This technique provided good linearity (R2 > 0.99), low detection limits (0.3-1.5 ng mL-1), high preconcentration factors (419-426), good relative recoveries (91.6-102 %), and high repeatability (RSD < 4.1 %) at optimized conditions (amount of sorbent: 15 mg; pH of solution: 7.0; and extraction time; 4 min). Ultimately, this approach was applied to determine triazole fungicides in different water and food samples.


Asunto(s)
Fungicidas Industriales , Microextracción en Fase Líquida , Nanocompuestos , Microextracción en Fase Sólida/métodos , Fungicidas Industriales/análisis , Verduras/química , Triazoles/análisis , Frutas/química , Agua/análisis , Celulosa/análisis , Ultrasonido , Nanocompuestos/análisis , Microextracción en Fase Líquida/métodos , Extracción en Fase Sólida , Límite de Detección
6.
Anal Methods ; 13(30): 3394-3401, 2021 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-34236068

RESUMEN

In this paper, a novel solid phase microextraction fiber based on Co3O4 quantum dot incorporated polyacrylamide-co-ethylene glycol dimethacrylate followed by corona discharge ion mobility spectrometry is presented for the trace determination of organophosphorus pesticides in environmental water samples. Ion mobility spectrometry is a comparatively inexpensive, well-known, robust, and easy to operate analytical instrument. This combination would provide a low-cost, fast, selective, and sensitive quantitative system for detection of organophosphorus pesticides. In order to obtain the best extraction efficiency, the optimization of parameters affecting this method was carried out. After optimization, a solution pH of 7.0, extraction temperature of 60 °C, adsorption temperature of 260 °C, extraction time of 30 min, stirring speed of 750 rpm, and ionic strength of 10% w/w were obtained. Consequently, the presented method showed low limits of detection (0.3-0.6 ng mL-1), excellent enrichment factors (PF = 221-263), good linearity (R2 > 0.995), and repeatabilities (intra-day: 3.4 to 4.8%) and (inter-day: 4.7 to 6.1%). The reproducibility (RSD% of fiber to fiber) was also investigated by analyzing three as-prepared fibers under the same conditions and was found to be less than 7.6%. Finally, the developed fiber was used for determination of organophosphorus pesticides in the field samples.


Asunto(s)
Plaguicidas , Puntos Cuánticos , Resinas Acrílicas , Metacrilatos , Compuestos Organofosforados , Plaguicidas/análisis , Reproducibilidad de los Resultados , Microextracción en Fase Sólida , Agua
7.
Mikrochim Acta ; 188(3): 73, 2021 02 06.
Artículo en Inglés | MEDLINE | ID: mdl-33550423

RESUMEN

Gelatin microsphere-coated Fe3O4@graphene quantum dots (Fe3O4@GQD@GM) were designed and synthesized as a novel sorbent via ultrasonic-assisted dispersive magnetic solid-phase extraction (UA-DMSPE) method. The synthesized sorbent was identified and confirmed by FT-IR, XRD, VSM, and SEM techniques. UA-DMSPE was combined with corona discharge ion mobility spectrometry for trace determination of desipramine, sertraline, and citalopram. Effective parameters were considered and optimized. The proposed method, under optimal conditions, showed excellent linearity in different concentration ranges (2-700 ng mL-1, R2 > 0.995), repeatability (RSD < 5.1%), good sensitivity (LODs in the range 0.6-1.5 ng mL-1), high preconcentration factor (PF = 207-218), and acceptable relative recoveries (93.5-101.8%). Eventually, this method was used to determine tricyclic antidepressants in various biological samples. Schematic presentation of the microextraction and monitoring of TCAs by ultrasonic-assisted dispersive magnetic solid phase microextraction-ion mobility spectrometry producer.


Asunto(s)
Antidepresivos Tricíclicos/aislamiento & purificación , Microesferas , Nanocompuestos/química , Puntos Cuánticos/química , Extracción en Fase Sólida/métodos , Adsorción , Antidepresivos Tricíclicos/sangre , Antidepresivos Tricíclicos/química , Antidepresivos Tricíclicos/orina , Citalopram/sangre , Citalopram/química , Citalopram/aislamiento & purificación , Citalopram/orina , Desipramina/sangre , Desipramina/química , Desipramina/aislamiento & purificación , Desipramina/orina , Gelatina/química , Grafito/química , Humanos , Límite de Detección , Fenómenos Magnéticos , Nanopartículas de Magnetita/química , Sertralina/sangre , Sertralina/química , Sertralina/aislamiento & purificación , Sertralina/orina
8.
Mikrochim Acta ; 187(4): 209, 2020 03 09.
Artículo en Inglés | MEDLINE | ID: mdl-32152680

RESUMEN

A new ultrasonic-assisted dispersive solid-phase extraction method using mesoporous nanosorbent composed of silica, graphene, and palladium (II) (M S/G@-SH@Pd (II)), coupled with corona discharge ion mobility spectrometry, was developed for trace determination of organophosphorus pesticides. Initially, the M S/G@-SH@Pd (II) nanosorbent was synthesized and characterized. Then, the nanosorbent was used for the sorption and extraction of organophosphorus pesticides. Under the optimized conditions (pH = 7.0, 15 mg of sorbent, 3 min extraction time, ethanol as desorption agent, 3 min centrifuge time), the proposed technique provided good linearity (R2 > 0.994), repeatability (RSD < 4.6%), low limits of detection (0.15-0.30 ng mL-1), excellent preconcentration factor (PF = 472-478), and high recoveries (93-94%). The method was applied to the determination of organophosphorus pesticides in real water samples. The sorbent was reused in 5 cycles without any considerable loss of activity. Graphical abstract Schematic presentation of design and synthesis of mesoporous nanosorbent composed of silica, graphene, and palladium (II) for ultrasound-assisted dispersive solid-phase extraction of organophosphorus pesticides prior to their quantitation by ion mobility spectrometry.

9.
Mikrochim Acta ; 186(4): 209, 2019 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-30826862

RESUMEN

An ultrasound-assisted method is described for dispersive solid phase extraction of trace levels of triazole fungicides. A sorbent was prepared from an N-heterocyclic carbene copper complex that was supported on ionic liquid-modified graphene oxide. The sorbent was characterized by scanning electron microscopy, transmission electron microscopy, Raman and FT-IR spectroscopy, energy-dispersive X-ray spectroscopy and elemental mapping. The capability of sorption and extraction is mainly based on complexation with Cu (I) ions. The variables affecting extraction were optimized. Following desorption with ethanol, the fungicides were quantified by corona discharge ion mobility spectrometry. Under optimized conditions (solution pH value: 7.0; amount of sorbent: 10 mg; extraction time: 3 min; desorption agent: ethanol), the technique provides good linearity (>0.994), repeatability (RSD < 4.1%), low limits of detection (0.18 ng.mL-1), excellent preconcentration factors (468-476) and high recoveries from spiked environmental water samples (92-94%). The sorbent can be reused over five cycles without significant loss of its activity. Graphical abstract Schematic presentation of design and synthesis of the N-heterocyclic carbene copper complex supported on ionic liquid-modified graphene oxide as a sorbent for triazole fungicides and its application in ultrasound-assisted dispersive solid phase extraction with ion mobility spectrometric detection.

10.
J Chromatogr A ; 1462: 27-34, 2016 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-27495366

RESUMEN

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.


Asunto(s)
Diazinón/análisis , Diazinón/orina , Extracción en Fase Sólida/métodos , Solventes/química , Contaminantes Químicos del Agua/análisis , Agua/química , Benzofenonas/química , Ionización de Llama , Humanos , Lagos/química , Límite de Detección , Aguas Residuales/química
11.
J Sep Sci ; 39(19): 3798-3805, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27514993

RESUMEN

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.


Asunto(s)
Acetanilidas/análisis , Acetanilidas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Aguas Residuales/química , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Cromatografía de Gases , Límite de Detección , Extracción en Fase Sólida/instrumentación
12.
Electrophoresis ; 36(24): 3034-41, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26383092

RESUMEN

In this paper, for the first time, surfactant-assisted electromembrane extraction coupled with capillary electrophoresis with UV detector was introduced for the extraction of acidic drugs from biological fluids. In this technique, in the presence of the nonionic surfactant in the donor phase, tendency of analyte ions into the supported liquid membrane (SLM) was increased. Naproxen and diclofenac were selected as model acidic drugs. In order to obtain the best extraction efficiency, several factors influencing the extraction efficiency were investigated. Optimal extractions were accomplished with 1-octanol as the SLM, 15 Volt dc potential as the driving force, pH 12 in acceptor solution, and 0.2 mmol/L Triton X-100 with pH 7.4 in donor solution. Equilibrium extraction conditions were obtained after 15 min of operation where the whole assembly agitated at 1000 rpm. Under the optimized conditions, preconcentration factors in the range of 176-184 and recoveries in the range of 88-92% were obtained. The applied method offers acceptable linearity with correlation coefficients higher than 0.9992. Limits of detection of 1.51 ng/mL and 2.42 ng/mL were obtained for naproxen and diclofenac, respectively. Finally, the developed method was successfully applied for the determination of naproxen and diclofenac in different matrices including plasma and urine samples.


Asunto(s)
Fraccionamiento Químico/métodos , Electroforesis Capilar/métodos , Tensoactivos/química , Humanos , Límite de Detección , Modelos Lineales , Membranas Artificiales , Preparaciones Farmacéuticas/sangre , Preparaciones Farmacéuticas/química , Preparaciones Farmacéuticas/orina , Reproducibilidad de los Resultados
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