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1.
Environ Sci Pollut Res Int ; 31(7): 10920-10933, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38216815

RESUMO

This study established the simultaneous determination of the selected endocrine-disrupting compounds (EDCs) and pesticides in rock, soil, water, moss, and feces samples collected from the Antarctic region. The spray-assisted droplet formation-based liquid phase microextraction (SADF-LPME) coupled to GC-MS system was developed and validated for the screening and monitoring of 29 selected EDCs and pesticides. Binary solvent system, 1:1 (v/v) dichlormethane: 1,2-dichloroethane mixture was employed as an extraction solvent and sprayed onto sample or standard solutions using a straightforward and practical spray apparatus. The factors affecting the extraction process such as extraction solvent type and ratio, extraction solvent volume (spray repetition), vortexing period, and sample pH were properly optimized. Analytical figures of the merit of the method were recorded under the optimal extraction/chromatographic conditions. The LOD, LOQ, and enhancement factor were in the range of 1.0 to 6.6 ng/g, 3.2 to 22.1 ng/g, and 3.7 to 158.9, respectively. The method demonstrated a good linear working range for all the selected analytes with proper coefficients of determination. The usability and reliability of the microextraction strategy was confirmed using seawater, moss, and soil samples, and the %recoveries were within an acceptable range (> 70%) for all examined samples. The environmental samples collected from the Horseshoe and Faure Islands of the Antarctica region were analyzed to assess the potential pollution of EDCs and pesticides. This method has the potential to be employed for the analysis of EDCs in routine analytical laboratories and for controlling and screening the organic pollutant content of different environmental samples.


Assuntos
Disruptores Endócrinos , Microextração em Fase Líquida , Praguicidas , Água/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Praguicidas/análise , Disruptores Endócrinos/análise , Regiões Antárticas , Microextração em Fase Líquida/métodos , Reprodutibilidade dos Testes , Solo , Solventes/química
2.
Environ Monit Assess ; 196(1): 77, 2023 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-38135867

RESUMO

This study employed simple polystyrene-coated magnetite nanoparticles (PS@MNPs)-assisted batch adsorption process for the removal of two antidepressant active ingredients (amitriptyline HCl and sertraline HCl) from hospital wastewater. Dominant parameters of the adsorption process including pH, adsorbent amount, and contact period were optimized through the univariate approach to enhance the adsorption efficiency. Upon reaching optimum adsorption conditions, equilibrium experiments were performed by spiking the adsorbates in hospital wastewater in the concentration range of 100-2000 µg/L. The concentrations of the adsorbates in the effluent were calculated using the matrix-matching calibration strategy to enhance the accuracy of quantification. A validated switchable solvent-based liquid phase microextraction (SS-LPME) method was employed to enrich the two active pharmaceutical ingredients (APIs) prior to sensitive determination with GC-MS (gas chromatography-mass spectrometry). The equilibrium data were mathematically modeled employing the Langmuir and Freundlich adsorption isotherm models. The isotherm constants were calculated, and the results showed that both the isotherm models fitted well with the experimental data. The efficient and simple batch adsorption strategy reported in this study was successfully employed to remove amitriptyline HCl and sertraline HCl from hospital wastewater at low concentrations.


Assuntos
Nanopartículas de Magnetita , Poluentes Químicos da Água , Amitriptilina/análise , Águas Residuárias , Princípios Ativos , Poliestirenos/análise , Sertralina/análise , Adsorção , Nanopartículas de Magnetita/química , Monitoramento Ambiental , Antidepressivos/análise , Poluentes Químicos da Água/análise , Cinética , Concentração de Íons de Hidrogênio
3.
Environ Monit Assess ; 195(2): 309, 2023 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-36652146

RESUMO

This study presents a simple, sensitive, and accurate method for the determination of nickel by flame atomic absorption spectrometry (FAAS). Prior to instrumental measurement, a deep eutectic solvent-based simultaneous complexation and preconcentration (DES-SCP) method was used to preconcentrate nickel from aqueous solution into measurable quantities. The efficiency of the extraction method was enhanced by forming a non-ionic complex of nickel using dithizone as ligand. By mixing the ligand with the DES extractant, simultaneous complexation and preconcentration of nickel were achieved in a single step. Under optimum conditions of the extraction method, the limit of detection (LOD) and the limit of quantification (LOQ) values were found to be 2.4 and 8.0 ng/mL, respectively. With respect to direct FAAS measurement, the developed method enhanced the sensitivity of nickel determination by about 169 folds. The accuracy and applicability of the developed method were evaluated by performing spike recovery experiments with lake water sampled from Antarctica. Satisfactory recovery results in the range of 94.0-113.7% were recorded and this validated the developed method as an efficient and green alternative for nickel determination.


Assuntos
Microextração em Fase Líquida , Níquel , Solventes/química , Níquel/análise , Regiões Antárticas , Solventes Eutéticos Profundos , Espectrofotometria Atômica/métodos , Lagos/análise , Ligantes , Microextração em Fase Líquida/métodos , Monitoramento Ambiental/métodos , Água/análise
4.
Anal Sci ; 38(6): 843-849, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35347676

RESUMO

A sensitive, accurate and simple analytical method was developed to determine cadmium by slotted quartz tube-flame atomic absorption spectrometry after preconcentration/extraction with polystyrene coated magnetic nanoparticles based dispersive solid phase extraction. The surface of Fe3O4 based magnetic nanoparticles was modified with polystyrene to yield higher selectivity and sensitivity in adsorption efficiency of cadmium. The nanoparticles were dispersed into the aqueous solution to extract/separate cadmium. Significant parameters of the method including magnetic nanoparticle amount, mixing effect, effect of ionic strength, eluent concentration and sonication period were optimized to achieve optimal conditions for the analyte. The limit of detection and quantification values of the developed method were found to be 0.62 and 2.1 ng/mL, respectively. Under the optimum conditions, enhancement of the detection power for cadmium were calculated as 102 folds for the developed method. The developed method was then applied to cigarette ash to test its accuracy and applicability. Total cadmium was found to be between 402 and 450 ng/g in the ashes of different cigarette brands commercially available in Turkey. The accuracy of quantifying cadmium in the complex ash samples was enhanced by using the matrix matching calibration strategy. The developed method provides sensitive and selective determination of cadmium at ng/mL levels even at complex cigarette ash samples. High percent recovery results (90-102%) were obtained from spiked real samples.


Assuntos
Nanopartículas de Magnetita , Produtos do Tabaco , Poluentes Químicos da Água , Cádmio/análise , Limite de Detecção , Nanopartículas de Magnetita/química , Poliestirenos , Quartzo/química , Extração em Fase Sólida/métodos , Espectrofotometria Atômica/métodos , Produtos do Tabaco/análise , Poluentes Químicos da Água/análise
5.
Food Chem ; 377: 132057, 2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35030340

RESUMO

This work reports the development of a simple, sensitive and low-cost analytical method for the trace determination of copper. A metal sieve-linked double syringe liquid phase microextraction method was used to preconcentrate copper into measurable quantities for FAAS system. The pressurized mixing offered by the automated syringe system and the sieve connector enhanced surface area for analyte and extraction solvent interaction, this significantly increased the extraction efficiency for copper. There was therefore no need for auxiliary organic solvents as disperser solvents for the extractant dichloromethane. The limits of detection and quantification, linear dynamic range and percent relative standard deviation values calculated for copper under optimum conditions of the method were 1.5 and 5.1 µg L-1, 5.0-500 µg L-1 and 8.4%, respectively. The developed method was successfully employed to determine copper (0.75-8.06 mg kg-1) in unspiked olive leaf samples.


Assuntos
Cobre , Olea , Extratos Vegetais/química , Cobre/análise , Limite de Detecção , Microextração em Fase Líquida/métodos , Olea/química , Solventes , Espectrofotometria Atômica
6.
Curr Med Imaging ; 18(2): 263-265, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34666645

RESUMO

BACKGROUND: Hepatic portal venous gas [HPVG] is not a common finding in daily practice. It is usually associated with mesenteric ischemia and bowel necrosis in adults. Combination of intratumoral gas in metastatic liver lesions with HPVG is quite rare and thought to be associated with chemotherapy-induced necrosis and infection of the necrotized metastasis Objective: Here we present a case of gastric adenocarcinoma with portal venous and intratumoral gas in metastatic liver lesions due to the infected necrosis. CASE PRESENTATION: The patient was presented to the emergency room with severe abdominal pain and septic condition after the second round of chemotherapy. Hepatic portal venous and intratumoral gas in metastatic liver lesions due to the infected necrosis of liver metastasis was detected in computed tomography images. There were no findings of mesenteric ischemia both clinically and radiologically. Massive intratumoral infected necrosis in metastatic liver lesions and fistulization to the right portal vein branches were detected on abdominopelvic CT. Secondary infection of the necrotic metastases and fistulization to portal vein branches was believed to cause the air in metastatic liver masses and portal venous gas. CONCLUSION: Infected necrosis of metastatic liver lesions and fistulizations to the portal venous structures is extremely rare. Clinicians and radiologists should be aware of such a rare complication because early detection is crucial for patient management..


Assuntos
Neoplasias Hepáticas , Isquemia Mesentérica , Neoplasias Gástricas , Adulto , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Isquemia Mesentérica/etiologia , Necrose/complicações , Veia Porta/diagnóstico por imagem , Neoplasias Gástricas/complicações , Neoplasias Gástricas/diagnóstico por imagem
7.
Curr Med Imaging ; 17(6): 790-797, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33371855

RESUMO

BACKGROUND: Ovarian granulosa cell tumors that originate from the sex cord-stromal cells represent 2% to 5% of all ovarian cancers. These tumors constitute two subgroups according to their clinical and histopathological features: juvenile granulosa cell tumors (JGCT) and adult granulosa cell tumors (AGCT). Granulosa cell tumor (GCT) is considered to be a low-grade malignancy with a favorable prognosis. METHODS: This case series includes four patients who were admitted to our university hospital and had an MRI examination within 5 years. RESULTS: The histopathological subtype of granulosa tumor was the adult type in 3 patients and juvenile type in 1 patient. Even though it is extremely rare, bone metastases were present in one of our patients. Liver metastases were also detected in one patient. The MRI examination of tumors revealed a heterogeneous solid mass that contained cystic components in 3 patients. In one of our patients, the tumor had a multiseptated cystic feature, and all of the tumors were ovoid or round with smooth margins. T1 signal hyperintensity, not suppressed on fat saturation sequences, was observed in 3 patients, which represents its hemorrhagic content. CONCLUSION: Even though granulosa cell tumor shows a wide spectrum in terms of tumor appearance, some common findings have been shown and especially a hemorrhagic content could be a clue for us. The tumor is known to have a good prognosis, but it may have an unpredictable clinical course, so close follow-up is greatly important.


Assuntos
Tumor de Células da Granulosa , Neoplasias Ovarianas , Feminino , Tumor de Células da Granulosa/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Neoplasias Ovarianas/diagnóstico por imagem
8.
Epileptic Disord ; 20(3): 200-203, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29905154

RESUMO

We describe the case of a patient with well-localized focal seizures originating from the medial parietal cortex. Seizures originated from area 7m, and findings revealed clear visuospatial semiological signs that may be used clinically to help diagnose similar cases of seizures in non-lesional patients.


Assuntos
Epilepsia/fisiopatologia , Lobo Parietal/fisiopatologia , Convulsões/fisiopatologia , Eletroencefalografia , Epilepsia/diagnóstico por imagem , Feminino , Humanos , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Lobo Parietal/diagnóstico por imagem , Convulsões/diagnóstico por imagem
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