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1.
Anal Chim Acta ; 1325: 342891, 2024 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-39244296

RESUMEN

Emerging pollutants pose an increasing threat to the environment and human well-being, requiring substantial progress in analytical methodologies. Dispersive micro-solid phase extraction (µ-dSPE) has proven successful in detecting and measuring these contaminants, particularly in trace quantities. However, challenges persist in achieving a uniform sorbent distribution and efficient separation from the sample matrix. To address these issues, effervescent-assisted dispersive micro-solid phase extraction (EA-µ-dSPE) was developed. This method uses on-site produced carbon dioxide as a dispersing agent, eliminating the need for vortexing or ultrasonication. Due to the sorbent dispersion in the sample solution, the contact surface between the analyte and the sorbent increases, resulting in increased extraction efficiency, reduced extraction time, and promotes of sustainability. Several parameters are critical to the successful execution of this procedure to extract the analytes, including the type and structure of sorbent, composition of dispersing agents, sorbent separation procedure, and type and properties of desorption solvents. The sorbent plays a critical role in successful extraction of emerging pollutants. It is clear that for the extraction of the analyte on the sorbent, proper interaction must be established between the analyte and the sorbent via physical and chemical interactions. This review thoroughly evaluates the underlying principles of the approach, its potential, and the significant advancements that have been documented. It explores the method's capacity to analyse and identify emerging pollutants, emphasising its potential across various sample matrices for enhanced pollutant identification and quantification.

2.
Daru ; 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136927

RESUMEN

BACKGROUND: Nilotinib (NIL) is a prescription medication employed in the treatment of specific types of leukemia, namely chronic myelogenous leukemia (CML). The determination of NIL levels in patients undergoing treatment for CML is of paramount importance for effective management of treatment and toxicity. Also, monitoring and controlling its level in wastewater sources could help scientists to identify potential hotspots of contamination and take appropriate measures to mitigate their impact on the environment and public health. OBJECTIVES: This study presents a D-µ-SPE technique utilizing two MOFs as adsorbents for the efficient detection of nilotinib in plasma and wastewater samples for the first time. METHODS: Two highly effective MOFs, MIL-101(Fe) and MIL-53(Al), were synthesized and applied as dispersive micro-solid phase extraction (D-µ-SPE) adsorbents for the extraction of nilotinib coupled with HPLC-UV in a short time of analysis. Experimental parameters affecting extraction efficacy such as adsorbent amount, ionic strength, pH value, adsorption-desorption time and type of elution solvent, were optimized. RESULTS: Under optimal experimental conditions, the linear dynamic was achieved in the range of 0.25-5.00 µg/mL in human plasma and 0.01-0.20 µg/mL in wastewater. The extraction recovery was in the range of 89.18-91.53% and 94.39-99.60% for nilotinib and MIL-101(Fe) and also 91.22-97.35% and 98.14-100.78% for nilotinib and MIL-53(Al) from human plasma and wastewater respectively. CONCLUSION: HPLC-UV determination of nilotinib after the D-µ-SPE method showed acceptable accuracy and precision in both plasma and wastewater. In comparison between the two adsorbents, the extraction procedure was easier and faster with MIL-53(Al) as the adsorbent.

3.
Anal Chim Acta ; 1319: 342955, 2024 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-39122271

RESUMEN

Solid-phase extraction (SPE) has gained an essential role in environmental analytical chemistry. Classic off-line SPE coupled with LC-MS/MS systems creates powerful analytical procedures for ultratrace analysis of contaminants of emerging concern (CECs) in water. But, being associated with tedious work and large consumption of materials, alternative SPE modes are becoming interesting. As so, the study focuses on development, evaluation, and overall comparison of established and novel SPE modes. Off-line SPE, dispersive micro SPE (DMSPE), and 'fast' single-pump on-line SPE were explored, using commercially available sorbents. Their efficiency was evaluated on their performance in water analysis of 20 multiclass CECs. Hydrophilic-lipophilic sorbent and mixture of C18/C8 sorbents were the best choice for off-line and DMSPE, respectively. All optimized SPE modes coupled with UHPLC-MS/MS reached environmentally-relevant limits of detection (LODs 0.1-12 ng L-1), acceptable repeatability (<20 % RSD), and exhibited less than ±30 % matrix effects in real river water sample. Among all, on-line SPE showed a potential to fully replace the well-established off-line SPE and even improve analytical performance. This was due to the best repeatability (<10 % RSD), automatization, simplicity, the highest multiplexing capacity, as well as comparable LODs of <2 ng L-1. DMSPE is, on the other hand, the most innovative and could be seen as a quick and green alternative to off-line SPE for determination of semi-to-nonpolar CECs, but within sub-10 ng L-1 range. Overall, the study shows workflow for the exploration of important and promising sample pretreatment techniques in water analysis. Comparison of the developed three SPE-UHPLC-MS/MS methods suggests that alternative SPE modes can compete with the well-established off-line SPE and can even improve the analysis quality if properly applied.

4.
J Chromatogr A ; 1733: 465259, 2024 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-39178659

RESUMEN

Aluminum-based metal organic framework composite containing ionic liquid was prepared and used as sorbent for extraction of sixteen polycyclic aromatic hydrocarbons in list of priority pollutants of United States Environmental Protection Agency before their analysis by gas chromatography/mass spectrometry. The dispersive micro solid-phase extraction method, known as a simple and fast method, was preferred as the extraction method. The optimized parameter conditions were 5 mL of sample solution, 10 min sonication by ultrasonic bath, 30 mg of sorbent, 30 °C extraction temperature, 0.1 mL of hexane as elution solvent with 5 min elution time. The suggested method presented that limit of detection and limit of quantification were in the range of 0.01-0.10 µg l-1, and 0.04-0.33 µg L-1, respectively. The intra-day and inter-day repeatability were within the ranges of 1.18-4.88 % and 1.02-5.06 %, respectively. The recoveries for polycyclic aromatic hydrocarbons in peach juice, cherry juice, tap water and rain water samples were obtained in the range of 84.9-99.9 % for spiked 5, 50 and 100 µg l-1 standard polycyclic aromatic hydrocarbons solution.


Asunto(s)
Jugos de Frutas y Vegetales , Cromatografía de Gases y Espectrometría de Masas , Líquidos Iónicos , Límite de Detección , Estructuras Metalorgánicas , Hidrocarburos Policíclicos Aromáticos , Contaminantes Químicos del Agua , Hidrocarburos Policíclicos Aromáticos/análisis , Hidrocarburos Policíclicos Aromáticos/aislamiento & purificación , Líquidos Iónicos/química , Jugos de Frutas y Vegetales/análisis , Estructuras Metalorgánicas/química , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Sonicación , Microextracción en Fase Sólida/métodos , Reproducibilidad de los Resultados
5.
J Chromatogr A ; 1732: 465192, 2024 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-39079363

RESUMEN

Metal-organic frameworks (MOFs) are a fascinating family of crystalline porous materials made up of metal clusters and organic linkers. In comparison with other porous materials, MOFs have unique characteristics including high surface area, homogeneous open cavities, and permanent high porosity with variable shapes and sizes. For these reasons, MOFs have recently been explored as sorbents in sample preparation by solid-phase extraction (SPE). However, SPE requires large amounts of sorbents and suffers from limited contact surfaces with analytes, which compromises extraction recovery and efficiency. Dispersive SPE (D-SPE) overcomes these limitations by dispersing the sorbents into the sample, which in turn increases contact with the analytes. Miniaturization of the microextraction procedure, particularly the amount of sorbent reduces the amount consumed of the organic solvent and shorten the time required to attain the equilibrium state. This may explain the reported high efficiency and applicability of MOFs in dispersive micro SPE (D-µ-SPE). This method retains all the advantages of solid phase extraction while also being simpler, faster, cheaper, and, in some cases, more effective in comparison with D-SPE. Besides, D-µ-SPE requires smaller amounts of the sorbents which reduces the overall cost, and the amount of waste generated from the analytical process. In this review, we discuss the applications of MOFs in D-µ-SPE of various analytes including pharmaceuticals, pesticides, organic dyes from miscellaneous matrices including water samples, biological samples and food samples.


Asunto(s)
Estructuras Metalorgánicas , Microextracción en Fase Sólida , Estructuras Metalorgánicas/química , Microextracción en Fase Sólida/métodos , Extracción en Fase Sólida/métodos , Adsorción , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química , Porosidad
6.
J Chromatogr A ; 1727: 464989, 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-38763085

RESUMEN

Ultrahigh-performance liquid chromatography coupled with high-field quadrupole Orbitrap high resolution mass spectrometry was used for the separation and determination of 20 antihistamines, and a dispersive micro solid-phase extraction procedure using high-performance absorbing material was developed as a sample preparation strategy for extracting 20 antihistamines from milk. Instrument conditions and key parameters influencing extraction efficiency were investigated to obtain an optimized method. The limit of detection for 20 antihistamines in milk using this method is 0.05 µg/L to 1.0 µg/L. Recoveries are between 80.7 % and 108.3 %, and the relative standard deviation is less than 15 %. It is suitable for confirmatory monitoring and quantitative analysis of 20 antihistamines in milk. The results show that antihistamines in milk may be noteworthy issues for human health and environmental pollution.


Asunto(s)
Antagonistas de los Receptores Histamínicos , Límite de Detección , Leche , Cromatografía Líquida de Alta Presión/métodos , Leche/química , Animales , Antagonistas de los Receptores Histamínicos/análisis , Antagonistas de los Receptores Histamínicos/aislamiento & purificación , Microextracción en Fase Sólida/métodos , Espectrometría de Masas/métodos , Bovinos , Reproducibilidad de los Resultados
7.
J Chromatogr A ; 1725: 464875, 2024 Jun 21.
Artículo en Inglés | MEDLINE | ID: mdl-38678692

RESUMEN

Ultrasonic-assisted dispersive micro solid phase extraction (UA-DMSPE) is proposed as a fast and easy technique for the extraction and preconcentration of methadone and tramadol from serum samples. Different sorbents including carbon nanotubes, oxidized carbon nanotubes, and TiO2 nanoparticles were compared to extract methadone and tramadol. The best performance was obtained using oxidized carbon nanotubes due to the strong affinity between the drugs and carbon nanotube adsorbents. Final analysis of drugs performed by using gas chromatography-mass spectrometric detection. Different parameters affecting the extraction efficiency, such as the sample volume, amount of adsorbent, desorption solvent type and volume, centrifugation time, and speed were investigated and optimized. The striking features of this technique are correlated to its speed and the small volumes of sample (about 1 mL), desorption solvent (about 50 µL), and adsorbent (about 0.001 g) for analysis of drugs, and finally, milder centrifugation conditions relative to the previously reported adsorbent. The optimal parameters were achieved as follows: pH value was set at 9, the sample volume was adjusted to 1200 µL, the amount of adsorbent used was 1 mg, the extraction time was set at 5 min, and the volume of the desorption solvent was adjusted to 50 µL. The limits of detections (0.5 and 0.8 ng mL-1) and quantifications (1.5 and 2.5 ng mL-1) were obtained for methadone and tramadol, respectively. The developed method also showed good repeatability, relative standard deviation (RSD) of 9.49 % and 7.47 % (n = 5), for the spiked aqueous solution at the concentration level of 10, 50, and 100 ng mL-1 for analytes, and linearity, R ≥ 0.9809. The results showed that UA-DMSPE is a quick, relatively inexpensive, and environmentally friendly alternative technique for the extraction of opiate drugs from serum samples.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas , Límite de Detección , Metadona , Microextracción en Fase Sólida , Tramadol , Tramadol/sangre , Metadona/sangre , Cromatografía de Gases y Espectrometría de Masas/métodos , Humanos , Microextracción en Fase Sólida/métodos , Nanotubos de Carbono/química , Reproducibilidad de los Resultados , Adsorción , Titanio
8.
J Environ Sci Health B ; 59(6): 285-299, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38686491

RESUMEN

In this paper, dispersive micro-solid phase extraction technique was developed for the purpose of extracting and preconcentrating organochlorine pesticide residues in juice samples before their separation and quantitative analysis by gas chromatography-mass spectrometry. A sorbent composed of a silica-supported Fe2O3-modified khat leftover biochar nanocomposite (SiO2-Fe2O3-KLBNC) was implemented in the process. To improve the dispersion of the sorbent in the solution, vortex mixer was employed. Experimental parameters influencing the performance of the method were optimized, and the optimal conditions were established. With these conditions, linear dynamic ranges ranged from 0.003 to 100.0 ng/mL were achieved, with a correlation coefficient (r2) ≥ 0.9981. The limits of detection and quantification, determined by signal-to-noise ratios of 3 and 10, respectively, were found to be in the ranges of 0.001-0.006 ng/mL and 0.003-0.020 ng/mL. Intra- and inter-day precision, values ranging from 0.3-4.8% and 1.7-5.2% were obtained, respectively. The matrix-matched extraction recoveries demonstrated favorable outcomes, falling within the range of 83.4-108.3%. The utilization of khat leftover as an adsorbent in contemporary sample preparation methodologies offers a cost-effective alternative to the currently available, yet expensive, adsorbents. This renders it economically viable, particularly in resource-constrained regions, and is anticipated to witness widespread adoption in the coming future.


Asunto(s)
Carbón Orgánico , Cromatografía de Gases y Espectrometría de Masas , Hidrocarburos Clorados , Nanocompuestos , Dióxido de Silicio , Carbón Orgánico/química , Nanocompuestos/química , Dióxido de Silicio/química , Hidrocarburos Clorados/análisis , Hidrocarburos Clorados/química , Compuestos Férricos/química , Catha/química , Microextracción en Fase Sólida/métodos , Residuos de Plaguicidas/análisis , Residuos de Plaguicidas/química , Jugos de Frutas y Vegetales/análisis , Contaminación de Alimentos/análisis
9.
Food Chem ; 447: 138848, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38458129

RESUMEN

This study presents a dispersive micro-solid phase extraction (D-µ-SPE) approach for extracting and determining of two organophosphorus pesticides (OPPs), including diazinon and chlorpyrifos as model analytes in various samples. For this purpose, we synthesized, characterized, and utilized magnetic multi-walled carbon nanotubes coated with poly 8-hydroxyquinoline (MWCNTs/Fe3O4@PHQ) as a novel sorbent. The impact of various parameters, including sorbent type, sample pH, sample volume, sorbent amount, desorption solvent (type and volume), extraction time, and ionic strength on the extraction efficiency was investigated and optimized. Following the extraction, the desorbed pesticides in acetone were analyzed using gas chromatography with an FID detector. Under the optimized experimental conditions, the proposed method showed excellent linearity in the range of 3-1000 µg/L, low detection limit (0.9-1.5 µg/L), good relative recoveries (86-101.5 %), and high precision (RSD < 6.5 %). Finally, the applicability of this method was evaluated by analyzing the target OPPs in a variety of real samples, and obtained satisfactory results.


Asunto(s)
Nanocompuestos , Nanotubos de Carbono , Plaguicidas , Plaguicidas/análisis , Agua/química , Compuestos Organofosforados/análisis , Verduras , Oxiquinolina , Frutas/química , Extracción en Fase Sólida/métodos , Fenómenos Magnéticos , Nanocompuestos/química , Límite de Detección
10.
Food Chem ; 445: 138733, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38387322

RESUMEN

Heavy metal pollution poses a significant health risk, necessitating regular environmental monitoring for public safety. Elevated nickel concentrations can disrupt ecosystems and impact human health. This study presents a nano-sorbent can be used for dispersive micro-solid phase extraction of nickel. The nano-sorbent was characterized using FT-IR, XRD, FESEM, BET, and BJH. It demonstrated remarkable efficiency due to its nanoscale properties, optimizing results in exceptional extraction performance with minimal interference from common ions. A flame atomic absorption spectrometer was utilized for all measurements. It has a low LOD (0.29 µg L-1) and RSDs% (7.3 % and 6 % intra-day and inter-day, respectively), minimal variation, and a precisely accurate correlation (0.997). It can be used on black tea, green tea, carrots, coffee beans, tuna fish, herring fish, tobacco, soil, natural water, and wastewater samples. The accuracy of the method was assessed by analyzing TMDA-64.3 fortified water and NIST 1573a tomato leaves certified reference materials.


Asunto(s)
Nanocompuestos , Nanodiamantes , Animales , Humanos , Níquel , Espectroscopía Infrarroja por Transformada de Fourier , Ecosistema , Agua , Extracción en Fase Sólida/métodos
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