Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 162
Filtrar
1.
Artigo em Inglês | MEDLINE | ID: mdl-38564965

RESUMO

In the present work, a new microextraction procedure combined with gas chromatography-mass spectrometry has been developed for the analysis of several aliphatic amines from urine sample. The sample preparation method was a continuous homogenous liquid phase microextraction that was based on in-situ preparation of 4-chlorophenol: choline chloride deep eutectic solvent. The deep eutectic solvent was prepared by passing the mixture of related compounds through a syringe barrel filled with exothermic salts (calcium chloride and potassium bromide). The released heat by dissolving the salts and increasing the solution ionic strength assists the formation of the deep eutectic solvent. The influence of various factors on the efficiency of the proposed procedure including salts amount, flow rate, pH, salting-out effect, and extraction solvent volume was studied. The calibration curves were linear broadly over the concentration range of 1.2-250 ng mL-1 with coefficient of determinations ≥0.996. The enrichment factors were in the range of 188-246 and the limits of detection and quantification were 0.16-0.37 and 0.56-1.2 ng mL-1, respectively. Based on the results, the offered method was sensitive, rapid, eco-friendly, and efficient for extracting and determining aliphatic amines in urine samples.


Assuntos
Microextração em Fase Líquida , Solventes/química , Microextração em Fase Líquida/métodos , Cromatografia Gasosa-Espectrometria de Massas/métodos , Solventes Eutéticos Profundos , Sais , Colina , Limite de Detecção
2.
Artigo em Inglês | MEDLINE | ID: mdl-38636134

RESUMO

Herein, a simple, sensitive, and reliable dispersive solid phase extraction was reported for the efficient extraction of sunitinib from biological samples. To facilitate the extraction of the desired analyte from urine and plasma samples, magnetic MIL-101Cr (NH2) @SiO2 @ NiFe2O4 was synthesized by a hydrothermal method and applied as an effective sorbent during the extraction process. After adsorption of the drug using 10 mg of MIL-101Cr (NH2) @ SiO2 @ NiFe2O4 nanoparticles through vortexing (1 min), the sorbent was separatedfrom the sample solution using a magnet. To eluate the drug, the sorbent containing the sunitinib was contacted with 100 µL dimethylformamide. The eluent was analyzed by high performance liquid chromatography-tandem mass spectrometry. Reasonable validation data consisting of low limits of detection (0.14, 0.35, and 0.70 ng mL-1 in deionized water, plasma, and urine) and quantification (0.48, 1.2, and 2.4 ng mL-1 in deionized water, plasma, and urine, respectively), a wide linear range of the calibration curve (0.48-200, 1.2-200, and 2.4-100 ng mL-1 in deionized water, plasma, and urine, respectively) good extraction recovery (76 %), and low relative standard deviations for inter- and intra-day precisions (6.9 %) were obtained by the method. Eventually, the proposed procedure was effectively implemented on both plasma and urine samples, yielding successful outcomes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38547699

RESUMO

In this research, a method known as a hollow fiber-liquid-phase microextraction was employed to extract and concentrate free metoprolol from plasma samples. The extracted analyte was subsequently determined using high-performance liquid chromatography coupled with a diode-array detector. Several parameters, including hollow fiber length, sonication time, extraction temperature, and salt addition, were investigated and optimized to enhance extraction efficiency. After extracting the analyte under optimum conditions from plasma samples, the enrichment factor and extraction recovery were 50 and 86 %, respectively. Moreover, the method exhibited detection and quantification limits of 0.41 and 1.30 ng mL-1, respectively. The analysis of real samples demonstrated satisfactory relative recoveries in the range of 91-99 %.


Assuntos
Microextração em Fase Líquida , Metoprolol , Microextração em Fase Líquida/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cloreto de Sódio , Sonicação
4.
ACS Omega ; 9(8): 9185-9201, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38434905

RESUMO

The streamlined water-leaching preconcentration method is introduced as a novel preconcentration method in this study. The approach has many benefits including low consumption of organic solvent and deionized water and operation time, energy-saving, no need for dispersion or evaporation, and implementation of more efficient preconcentration. Also, a methodological study was done on the synthesis of (Fe/Co) bimetallic-organic framework that eased the synthesis procedure, decreased its time, and enhanced its analytical performance by increasing its surface area, total pore volume, and average pore diameter parameters. To perform the extraction, bi-MOF particles were added into the solution of interest enriched with sodium sulfate. After vortexing to adsorb the analytes, centrifugation isolated the sorbent particles. A microliter-volume of acetonitrile and 1,2-dibromoethane mixture was used for desorption aim via vortexing. After the separation of the organic phase and transferring it into a conical bottom glass test tube, a milliliter volume of sodium chloride solution was applied to leach the organic phase. A gas chromatograph equipped with a flame ionization detector was applied for the injection of the extracted phase. The method was applied for the extraction and preconcentration of some pesticides from juice samples. Wide linear ranges (5.44-1600 µg L-1), low relative standard deviations (3.1-4.5% for intra- (n = 6) and 3.5-5.2% for interday (n = 4) precisions), high extraction recoveries (61-95%), enrichment factors (305-475), and low limits of detection (0.67-1.65 µg L-1) and quantification (2.21-5.44 µg L-1) were obtained for the developed method.

5.
Anal Methods ; 16(11): 1593-1602, 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38404220

RESUMO

In this study, a sample preparation procedure based on salt-induced homogeneous liquid-liquid extraction performed in a narrow-bore tube was used for the preconcentration and extraction of Zn(II), Cu(II), and Cd(II) ions from honey samples. To perform the procedure, a mixture of working solution containing sodium chloride, acetonitrile, and a synthesized deep eutectic solvent (as an extraction solvent) was transferred into a narrow tube filled with solid sodium chloride up to a specific level. As the solution flowed through the tube, tiny droplets of the extraction solvent were formed at the boundary between the solution and salt layer. The droplets moved upwards in the tube and eventually collected as a distinct layer on the top of the solution. The separated phase was removed and dispersed into ionized water. After centrifugation, tiny droplets of the extraction solvent containing the analytes were sedimented at the bottom of the tube. The concentrated analytes were measured using flame atomic absorption spectrophotometry. The linear ranges and extraction recoveries were obtained in the ranges of 1.5-100 µg kg-1 and 89.6-94.8%, respectively. The detection limits ranged from 0.35 to 0.48 µg kg-1. Low relative standard deviations (C = 10 µg L-1, n = 6) of 3.1, 2.8, and 3.4% for Zn(II), Cu(II), and Cd(II), respectively, were obtained. Finally, the optimized method was successfully used in determination of concentration of the selected heavy metal ions in various honey samples.


Assuntos
Mel , Microextração em Fase Líquida , Solventes , Cloreto de Sódio , Cádmio , Solventes Eutéticos Profundos , Microextração em Fase Líquida/métodos , Extração Líquido-Líquido/métodos , Cloreto de Sódio na Dieta , Zinco
6.
Artigo em Inglês | MEDLINE | ID: mdl-38252747

RESUMO

A magnetic dispersive solid phase extraction method combined with solidification of floating organic droplet-based dispersive liquid-liquid microextraction has been validated for the extraction of polycyclic aromatic hydrocarbons from honey samples. For this purpose, a carbonised cellulose-ferromagnetic nanocomposite was used as a sorbent through the magnetic dispersive solid phase extraction. For preparation of the sorbent, first, carbonised cellulose nanoparticles were created by treating cellulose filter paper with concentrated solution of sulfuric acid. Then, the prepared nanoparticles were loaded onto Fe3O4 nanoparticles through coprecipitation. In the extraction process, first, a few mg of the sorbent was added to the diluted honey solution and dispersed in it using vortex agitation. The particles were then separated and the adsorbed analytes were eluted with an organic solvent. The eluent was taken and after mixing with a water-immiscible extraction solvent was used in the following solidification of floating organic droplet-based dispersive liquid-liquid microextraction procedure. By performing the extraction process under the obtained optimum conditions, low limits of detection (0.08-0.17 ng g-1) and quantification (0.27-0.57 ng g-1), satisfactory precision (relative standard deviations ≤ 5.0%), and wide linear range (0.57-500 ng g-1) with great coefficients of determination (r2≥ 0.9986) were obtained.


Assuntos
Mel , Microextração em Fase Líquida , Hidrocarbonetos Policíclicos Aromáticos , Cromatografia Gasosa-Espectrometria de Massas , Microextração em Fase Líquida/métodos , Hidrocarbonetos Policíclicos Aromáticos/análise , Extração em Fase Sólida/métodos , Solventes , Celulose , Fenômenos Magnéticos
7.
Artigo em Inglês | MEDLINE | ID: mdl-38211390

RESUMO

Tacrolimus is a potent immunosuppressive drug used in the prevention of tissue rejection. It has a narrow therapeutic index. Therefore, the determination of its concentration in biological fluids like plasma and urine is a very crucial issue. In this research, tacrolimus concentrations in plasma and urine samples were determined with a dispersive solid phase extraction procedure coupled to high-performance liquid chromatography-tandem mass spectrometry. For this purpose, a curcumin modified metal-organic framework was synthesized and used in extraction procedure. Tacrolimus was adsorbed onto the sorbent surface with aid of vortexing. Then, the adsorbed tacrolimus was eluted by a suitable solvent. Important parameters in extraction procedure were optimized by "one-variable-at-a-time" approach and reported as below: sorbent amount, 10 mg; sample solution pH, 2; agitation mode, vortexing; adsorption and desorption times, 1 min, and eluent (volume), methanol (200 µL). Under the optimized conditions and according to the International Council for Harmonization guidelines, the validation of the method was performed, and the results showed acceptable accuracy and precision (relative standard deviations ≤14 %), good linearity in a wide range (4-200 ng mL-1), and low limits of detection (1.2 ng mL-1 in plasma and 0.34 ng mL-1 in urine) and quantification (4.7 ng mL-1 in plasma and 1.12 ng mL-1 in urine). Finally, the validated method was successfully applied for the determination of tacrolimus in the plasma samples of the patients.


Assuntos
Curcumina , Estruturas Metalorgânicas , Nanocompostos , Humanos , Estruturas Metalorgânicas/química , Tacrolimo , Espectrometria de Massas em Tandem/métodos , 60705 , Cromatografia Líquida , Extração em Fase Sólida/métodos , Cromatografia Líquida de Alta Pressão/métodos
8.
Anal Chim Acta ; 1287: 342062, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38182369

RESUMO

BACKGROUND: Herein, a new extraction procedure based on in-situ formation of carbon dioxide-incorporated solid sorbent was introduced for dispersive solid phase extraction of phenolic compounds from aqueous samples. In this study, incorporation of carbon dioxide into the structure of a diamine led to the formation of a solid compound in the sample solution that adsorbed the analytes. RESULTS: The sample solution was mixed with isophorone diamine and placed under carbon dioxide stream. By doing so, isophorone diamine reacted with carbon dioxide and produced a carbamic acid analogue. It was dispersed into the sample solution as tiny particles that adsorbed the analytes. The adsorbed analytes were eluted by a volatile organic solvent and concentrated more by the vaporization of the eluate. The extraction procedure was done at low temperature to limit the releasing carbon dioxide from the produced compound. To obtain the reliable results, the method was validated and the obtained limits of detection and quantification were in the ranges of 0.29-41 and 0.96-1.3 ng/mL, respectively. Acceptable relative standard deviation (≤7.3%) and coefficient of determination (≥0.994) values confirmed the method repeatability and linearity. High enrichment factors (410-435) and extraction recoveries (82-87%) were attained with the introduced method. SIGNIFICANCE AND NOVELTY: In this work, a chemical reaction was done between isophorone diamine and carbon dioxide in solution. The produced product (sorbent) was insoluble in solution and dispersed in whole parts of the solution as tiny particles. A high contact area between the sorbent and analytes provided high extraction efficiency for the analytes. The method was successful utilized in determining target analytes in real samples and the matrix effect of the samples had no important effect on the obtained results.

9.
J Pharm Biomed Anal ; 239: 115874, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38029702

RESUMO

In this work, a simple and inexpensive dispersive solid phase extraction method using SiO2 @MCM-41-Co3O4 yolk shell as a sorbent was developed for the extraction of favipiravir from plasma samples. The sorbent was synthesized with a simple and novel method. Optimization of the extraction procedure was performed using one parameter at a time strategy. For selective measurement of favipiravir in real samples, multiple reaction monitoring mode in high-performance liquid chromatography-tandem mass spectrometry was used. The synthesized sorbent presented a high adsorption capacity for favipiravir due to its mesoporous structure and different interactions. After optimization of effective parameters including the amount of sorbent, pH, and adsorption and desorption times, the analytical parameters of the method were evaluated. The developed method exhibited a wide linear range from 0.50 to 1000 µg/L. The detection limit and quantification limit of the method were 0.15 and 0.50 µg/L, respectively. The relative standard deviation of the method was obtained by using intra- and inter-day tests, and in both cases, it was less than 6.0%. Finally, the method was successfully used to measure favipiravir in plasma samples with relative recoveries in the range of 87-105%.


Assuntos
COVID-19 , Espectrometria de Massas em Tandem , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Espectrometria de Massas em Tandem/métodos , Dióxido de Silício/química , Limite de Detecção , Extração em Fase Sólida/métodos
10.
J Pharm Biomed Anal ; 240: 115926, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38142500

RESUMO

For the first time in this study, a microextraction method was developed to perform follicular fluid safety assessment analysis. The drastic importance of follicular fluid safety on the proper nourishment and development of oocytes caused the development of the present method. Since women are regularly exposed to parabens through cosmetics, healthcare, and hygienic products, the infection of body fluids is probable in long-term exposures. Also, for the first time, MIL-68 (In) was applied in an analytical method. Moreover, a new method called in-situ effervescence-boosted dispersive liquid-liquid microextraction was adopted for the simultaneous derivatization and preconcentration of the target parabens. To perform the method, 25 mg of MIL-68 (In) was dispersed into the solution of follicular fluid by vortexing. Then, 1.0 mL of 2-propanol was used to elute the analytes from the absorbent via vortexing. The analyte-enriched organic phase was mixed with 100 µL of acetic anhydride (derivatization agent) and 27 µL 1,2-dibromoethane (extraction solvent) which was swiftly injected into a sodium carbonate solution. Following the centrifugation, the extraction solvent was sedimented at the bottom of a conical bottom glass test tube and an aliquot of it was injected into a gas chromatograph equipped with a flame ionization detector. Wide linear ranges (120-25000 µg L-1), satisfactory extraction recoveries (31-79%) and enrichment factors (31-79), and appreciable limits of detection (7-36 µg L-1) and quantification (25-120 µg L-1) were recorded. The high surface area of MIL-68 (In) (608.82 m2 g-1) and its significantly low average pore diameter (13.829 A°) provide an ideal platform for the extraction of parabens from the complex matrix of follicular fluid.


Assuntos
Microextração em Fase Líquida , Parabenos , Humanos , Feminino , Parabenos/análise , Microextração em Fase Líquida/métodos , Líquido Folicular/química , Solventes/análise , Extração em Fase Sólida/métodos
11.
Sci Rep ; 13(1): 21304, 2023 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042936

RESUMO

This study was the first-ever attempt to apply MIL-68 (Ga) in developing an analytical method. The method extracts and preconcentrates some parabens from mouthwash and hydrating gel samples. The variable extraction parameters were optimized, and the figures of merit were documented. Avogadro software was used besides discussing intermolecular interactions to clarify the absorption process. ComplexGAPI software was also exploited to assess the greenness of the method. After the derivatization of the parabens using acetic anhydride in the presence of sodium carbonate, sodium chloride was added to the solution and vortexed to dissolve. A few milligrams of MIL-68 (Ga) were added into the solution and vortexed. Centrifugation separated the analyte-loaded absorbent, which was treated with mL volume of methanol through vortexing for desorption aim. A few microliters of 1,2-dibromoethane were merged with the methanolic phase and injected into a sodium chloride solution. One microliter of the extracted phase was injected into a gas chromatograph equipped with a flame ionization detector. High enrichment factors (200-330), reasonable extraction recoveries (40-66%), wide linear ranges (265-30,000 µg L-1), and appreciable coefficients of determination (0.996-0.999) were documented. The applicability of dispersive solid phase extraction for extracting polar analytes, imposing no additional step for performing derivatization, the capability of MIL-68 (Ga) for the absorption of both derivatized and non-derivatized parabens, the use of only 10 mg absorbent, and one-pot synthesis besides no high temperature or long reaction time in the sorbent provision are the highlights of the method.


Assuntos
Parabenos , Cloreto de Sódio , Parabenos/análise , Extração em Fase Sólida/métodos , Cromatografia Gasosa/métodos , Metanol
12.
Anal Methods ; 15(46): 6482-6491, 2023 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-37987503

RESUMO

This study was focused on the development of a sensitive, reliable, and efficient extraction procedure for the determination of amphetamine and methamphetamine utilized in the adulteration of creatine sports supplements. The separation and detection of the analytes were conducted using the gas chromatography-flame ionization detection method. In this study, the analytes were extracted from a supplement powder into a proper solvent by sonication. Then, the extract was mixed with butyl chloroformate to obtain their butylated derivatives and then concentrated by a dispersive liquid-liquid microextraction procedure. The method was performed in a short time. Under optimized extraction conditions, a linear range of 2.01-500 ng g-1 was obtained by a coefficient of determination ≥0.996. Low detection (0.22 ng g-1 and 0.61 ng g-1 for amphetamine and methamphetamine, respectively) and quantification (0.73 ng g-1 and 2.01 ng g-1 for amphetamine and methamphetamine, respectively) limits, good precision (relative standard deviations ≤8.2%), and high extraction recoveries (79% and 86% for amphetamine and methamphetamine, respectively) were achieved. The usefulness of the method in the analysis of the target compounds was confirmed by studying the matrix effect and analysis of the analytes in different real samples.


Assuntos
Microextração em Fase Líquida , Metanfetamina , Metanfetamina/análise , Anfetamina/análise , Creatina/análise , Microextração em Fase Líquida/métodos , Cromatografia Gasosa/métodos
13.
Anal Methods ; 15(42): 5655-5665, 2023 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-37855170

RESUMO

Herein, an air-agitation liquid-liquid microextraction procedure was developed for the extraction of several polycyclic aromatic hydrocarbons from edible oil samples. In this study, the extraction procedure was achieved using a new magnetic deep eutectic solvent as the extraction solvent, in which there was no need for centrifugation. To enhance the rate of extraction of the analytes from the samples, the method was promoted by the use of surfactant addition. The extracted analytes were determined by high-performance liquid chromatography with a diode array detector. The influence of various parameters on the extraction efficiency was studied by response surface methodology using a central composite design. Under optimal conditions, linear calibration curves for the target analytes were achieved in the range of 0.43-250 ng g-1. The limits of detection and quantification were in the ranges of 0.04-0.13 and 0.13-0.43 ng g-1, respectively. The repeatability of the method in terms of intra- and inter-day precision was ≤4.7% and ≤6.7%, respectively. The extraction recovery of the method ranged from 75 to 88%. The obtained results show that the proposed method is efficient for the analysis of the target analytes in various oil samples without obvious matrix effects. Pyrene was found in olive oil at a concentration of 42 ng g-1.


Assuntos
Microextração em Fase Líquida , Hidrocarbonetos Policíclicos Aromáticos , Surfactantes Pulmonares , Solventes/química , Hidrocarbonetos Policíclicos Aromáticos/análise , Cromatografia Líquida de Alta Pressão/métodos , Solventes Eutéticos Profundos , Tensoativos/análise , Microextração em Fase Líquida/métodos , Surfactantes Pulmonares/análise , Fenômenos Magnéticos
14.
RSC Adv ; 13(43): 30378-30390, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37854488

RESUMO

The first-ever attempt to apply nickel gallic acid metal-organic framework (NiGA MOF) in analytical method development was done in this research by the extraction of some plasticizers from aqueous media. The greenness of the method is owing to the use of gallic acid and nickel as safe reagents and water as the safest solvent. Low boiling point solvents were applied as desorption solvents that underwent temperature-assisted evaporation in the preconcentration step. Performing the evaporation using a low-temperature water bath for a short period of time streamlines the preconcentration section. Into the solution of interest enriched with sodium sulfate, a mg amount of NiGA MOF was added alongside vortexing to extract the analytes. Following centrifugation and discarding the supernatant, a µL level of diethyl ether was added onto the analyte-loaded NiGA MOF particles and vortexed. The analyte-enriched diethyl ether phase was transferred into a conical bottom glass test tube and located in a water bath set at the temperature of 35 °C under a laboratory hood. After the evaporation, a µL level of 1,2-dibromoethane was added to the test tube and vortexed to dissolve the analytes from the inner perimeter of the tube. One microliter of the organic phase was injected into a gas chromatograph equipped with flame ionization detection. Appreciable extraction recoveries (61-98%), high enrichment factors (305-490), low limits of detection (0.80-1.74 µg L-1) and quantification (2.64-5.74 µg L-1), and wide linear ranges (5.74-1000 µg L-1) were obtained at the optimum conditions.

16.
J Sep Sci ; 46(21): e2300323, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37691072

RESUMO

This study introduces a reliable and inexpensive magnetic dispersive solid phase extraction to extract imipramine and its primary metabolite (desipramine) from urine samples. To accomplish this aim, Fe3 O4 magnetic nanoparticles were synthesized by sonication, subsequently, polycarbonate was precipitated gradually onto the surface of them to form the adsorbent. Extraction recoveries of 85% and 76%, enrichment factors of 57 and 51, limits of detection of 2.5 and 2.8 µg/L, and limits of quantification of 8.3 and 9.3 µg/L were obtained for imipramine and desipramine under the optimal conditions, respectively. In addition, relative standard deviations for intra- (n = 6) and inter-day (n = 5) precisions at two concentrations (50 and 100 µg/L of each analyte) were less than or equal to 4%. Short extraction time, good repeatability, high enrichment factors, and simplicity are the main advantages of the proposed method.


Assuntos
Imipramina , Nanopartículas de Magnetita , Desipramina , Extração em Fase Sólida , Cromatografia Líquida de Alta Pressão , Fenômenos Magnéticos
17.
Anal Sci ; 39(11): 1901-1908, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37594680

RESUMO

In this research, a dispersive solid phase extraction procedure based on changing the solubility of octadecylamine with pH was proposed to determine Ag+ ions in different water samples. For this purpose, first, the pH of sample solution containing the analyte was adjusted to 10.5. Then desired volume of the octadecylamine dissolved in acidic solution was injected into the solution. Because of the low solubility of octadecylamine in alkaline solution, a cloudy state was formed. The produced octadecylamine particles acted as a complexing agent for Ag+ ions and adsorbent for the formed complex. The obtained cloudy solution was centrifuged and the sedimented particles were removed and dissolved in a diluted nitric acid solution. It was injected into a flame atomic absorption spectrometry to determine the extracted amounts of the analyte. The effect of important parameters such as the amount of octadecylamine, volume of nitric acid, and centrifugation and vortexing conditions on the extraction efficiency of the procedure was studied and optimized. In optimal conditions, the developed method showed a linear range of 0.50-200 µg L-1. The limits of detection and quantification were 0.18 and 0.50 µg L-1, respectively. Extraction recovery was 93.6%. The relative standard deviations were less than 4%. The effectiveness of the method was investigated by determination of Ag+ ions in water and wastewater samples.

18.
Anal Methods ; 15(34): 4321-4330, 2023 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-37606547

RESUMO

In this study, a new homogeneous liquid-liquid microextraction method using a deep eutectic solvent has been developed for the extraction of Cu(II) and Pb(II) ions in dairy products. Initially, the deep eutectic solvent was synthesized using choline chloride and p-chlorophenol and used as the extraction solvent. The synthesized solvent was soluble in milk at 70 °C and its separation from the sample was performed by decreasing the temperature. By cooling, a cloudy solution was formed due to the low solubility of the solvent at low temperatures. On centrifugation, the fine droplets of the solvent containing the analytes settled at the bottom of the tube by sedimentation. The enriched analytes were determined by flame atomic absorption spectrometry. The effect of some important parameters such as the amount of protein precipitating agent , complexing agent amount, extraction solvent volume, salt addition, pH, and temperature on the extraction efficiency of the method was studied and optimized. Under the optimal conditions, the linear ranges of the method for Cu(II) and Pb(II) ions were obtained in the ranges of 0.10-50 and 0.50-50 µg L-1 with detection limits of 0.04 and 0.18 µg L-1, respectively. The repeatability of the developed method, expressed as relative standard deviation, was determined to be 3.2 and 3.9% for Cu(II) and Pb(II) ions, respectively. Finally, by determining the concentration of Cu(II) and Pb(II) ions in milk, doogh, and cheese samples, the feasibility of the method was successfully confirmed with the extraction recoveries of 95.9 and 92.1% for Cu(II) and Pb(II) ions, respectively.


Assuntos
Cobre , Microextração em Fase Líquida , Animais , Temperatura Alta , Solventes Eutéticos Profundos , Chumbo , Leite , Íons
19.
Anal Methods ; 15(33): 4187-4193, 2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37581438

RESUMO

In the current study, salt- and pH-induced homogeneous dispersive solid phase extraction was developed using albumin as a sorbent for the extraction of some pesticides (diazinon, diniconazole, haloxyfop-R-methyl, and hexaconazole) from fruit juice of orange, pomegranate, and barberry. The extracted analytes were more concentrated by dispersive liquid-liquid microextraction to obtain high enrichment factors and low detection limits prior to their determination by gas chromatography-mass spectrometry. In the extraction process, human serum albumin solution was added to the sample solution at the µL-level and a homogeneous solution was obtained. Then, albumin was precipitated into the solution by adding an inorganic salt and decreasing the solution pH. By doing so, the analytes were adsorbed by albumin effectively due to their high adsorption capacity and large surface area. Following this, the pesticides were eluted from the albumin sorbent using an elution solvent and used in a dispersive liquid-liquid microextraction step. Under the optimum extraction conditions, low limits of detection and quantification were achieved in the ranges of 0.02-0.04 and 0.07-0.13 ng mL-1, respectively. The calibration curves were linear in the range of 0.13-250 ng mL-1. Relative standard deviation as a criterion for precision and the method repeatability were in the ranges of 2.9-4.2% for intra- (n = 5, C = 5 or 50 ng mL-1) and 3.2-5.2% for inter-day (n = 5, 50 ng mL-1) precisions. The enrichment factors and extraction recoveries were in the ranges of 390-460 and 78-92%, respectively. Finally, the offered procedure was applied for the analysis of pesticide residues in some fruit juice samples.


Assuntos
Resíduos de Praguicidas , Praguicidas , Humanos , Praguicidas/análise , Sucos de Frutas e Vegetais/análise , Resíduos de Praguicidas/análise , Cloreto de Sódio/análise , Extração em Fase Sólida/métodos , Cloreto de Sódio na Dieta/análise , Albuminas/análise
20.
RSC Adv ; 13(31): 21673-21684, 2023 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-37476043

RESUMO

For the first time, this research introduces an analytical application of Ni-MOF-I, which was used as an adsorbent in a dispersive micro solid phase extraction procedure followed by dispersive liquid-liquid microextraction for the extraction and preconcentration of seven pesticides from different fruit juices. Also, Ni-MOF-I was synthesized by a new and green method with many advantages over the previously published synthesis procedures. For example, effortless and green synthesis, no need for autoclaves and ovens, and elimination of organic solvent usage are the main highlights. The synthesized Ni-MOF-I was characterized by applying nitrogen adsorption/desorption, energy-dispersive X-ray, scanning electron microscopy, Fourier transform infrared spectrophotometry, and X-ray diffraction analyses. The studied pesticides were extracted and preconcentrated by the proposed method. Then, the extracted analytes in the sedimented organic phase were injected into a gas chromatography-flame ionization detector. Acceptable analytical results such as low limits of detection (0.15-0.60 µg L-1) and quantification (0.50-2.0 µg L-1), reasonable extraction recoveries (51-80%), high enrichment factors (255-400), satisfactory relative standard deviation values of 4.8-7.2% (intra-day precision, n = 6) and 5.3-7.5% (inter-day precision, n = 4), and wide linear ranges were obtained. The proposed method can be introduced as an effective analytical technique based on Ni-MOF-I for the analysis of different pesticides in fruit beverages.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...