Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Inflammation ; 45(4): 1548-1558, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35304668

RESUMEN

The dysfunction of airway smooth muscle cells (ASMCs) is one of the key factors in the pathogenesis of asthma. How miR-98-5p works in asthma has not been completely elucidated. This work focused on how miR-98-5p functions in the proliferation and migration of human ASMCs treated with interleukin-13 (IL-13). MiR-98-5p expression in plasma of asthmatic patients and IL-13-stimulated ASMCs was probed by quantitative real-time polymerase chain reaction (qRT-PCR). RAS-relevant C3 botulinum toxin substrate 1 (RAC1) protein expression in ASMCs was assessed by Western blot. The growth of ASMCs was measured by cell counting kit-8 (CCK-8) assay and 5-ethynyl-2'-deoxyuridine (EdU) assay. The migration of ASMCs was examined by Transwell assay. Besides, the apoptosis of ASMCs was analyzed by flow cytometry. The targeting relationship between miR-98-5p and RAC1 3'-UTR was verified by a dual-luciferase reporter gene assay. MiR-98-5p expression was reduced in patients' plasma and IL-13-stimulated ASMCs, and RAC1 expression was upregulated in ASMCs treated with IL-13. MiR-98-5p overexpression inhibited IL-13-induced proliferation and migration of ASMCs while promoting the apoptosis. The opposite result was observed after inhibiting miR-98-5p expression. Besides, RAC1 was identified as a direct downstream target of miR-98-5p in ASMCs. The restoration of RAC1 expression counteracted the impacts of miR-98-5p overexpression on IL-13-stimulated proliferation, migration, and apoptosis of ASMCs. MiR-98-5p inhibits IL-13-induced proliferation and migration and accelerates the apoptosis of ASMCs by downregulating RAC1 expression.


Asunto(s)
Asma , MicroARNs , Asma/patología , Movimiento Celular , Proliferación Celular/fisiología , Humanos , Interleucina-13/metabolismo , Interleucina-13/farmacología , MicroARNs/metabolismo , Miocitos del Músculo Liso/metabolismo , Proteína de Unión al GTP rac1/metabolismo
2.
Bioengineered ; 13(3): 5396-5406, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35172671

RESUMEN

The excessive proliferation and the deposition of extracellular matrix (ECM) of airway smooth muscle (ASM) cells facilitates airway remodeling in asthma. This study explores how microRNA-15b-5p (miR-15b-5p) functions in modulating the proliferation, migration, inflammatory response, and ECM deposition of ASM cells. MiR-15b-5p and yes-associated protein 1 (YAP1) mRNA expression levels in tumor necrosis factor alpha (TNF-α)-induced ASM cells were, respectively, examined by real-time quantitative polymerase-chain reaction. Besides, the proliferative ability and migrative potential of ASM cells were examined by cell counting kit-8 assay, 5-bromo-2 '-deoxyuridine assay, and transwell assays, respectively. Interleukin-6 and interleukin-8 levels in ASM cells were detected by enzyme-linked immunosorbent assay. YAP1, collagen I, and collagen III expressions in ASM cells were detected by Western blot. With dual-luciferase reporter gene assay, the relations between miR-15b-5p and YAP1 3'UTR in ASM cells was examined. MiR-15b-5p expression level was reduced in ASM cells treated with TNF-α. MiR-15b-5p repressed TNF-α-initiated growth and migration of ASM cells and also suppressed IL-6 and IL-8 secretion, and inhibited collagen I and collagen III expressions in ASM cells. Furthermore, it was validated that YAP1 was a downstream target of miR-15b-5p in ASM cells. Notably, YAP1 overexpression attenuated the inhibitory effects of miR-15b-5p up-regulation on the proliferation, migration, and inflammatory response, as well as ECM deposition of TNF-α-induced ASM cells. In conclusion, miR-15b-5p/YAP1 axis modulates the growth, migration, inflammatory response, and ECM deposition of ASM cells, thus participating in the pathogenesis of asthma.


Asunto(s)
Asma , MicroARNs , Asma/metabolismo , Proliferación Celular/genética , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Miocitos del Músculo Liso/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Proteínas Señalizadoras YAP
3.
Bioengineered ; 12(2): 12767-12777, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34747300

RESUMEN

Dysregulated circular RNAs (circRNAs) are involved in the progression of non-small cell lung cancer (NSCLC). However, the role of has_circ_0002360 (circ_0002360) in NSCLC has rarely been reported. In this study, circ_0002360 expression in NSCLC tissues and cell lines was measured using microarray data and quantitative real-time PCR (qRT-PCR). After gain-of-function and loss-of-function, cell models were established; 5-bromo-2-deoxyuridine (BrdU) and transwell assays were conducted to detect NSCLC cell growth, migration, and invasion. What is more, bioinformatic analysis and dual-luciferase reporter assay were adopted to show how circ_0002360, microRNAs (miR-127-5p, miR-145-5p, miR-585-3p, and miR-758-3p), and matrix metalloproteinase 16 (MMP16) 3'UTR interact with each other. Western blotting was executed to probe the regulatory effects of circ_0002360 and these miRNAs on MMP16 protein expression in NSCLC cells. We found that circ_0002360 expression was raised in NSCLC tissues. High circ_0002360 expression predicted a short overall survival time for NSCLC patients. Circ_0002360 overexpression promoted NSCLC cell proliferative, migrative, and invasive abilities, and circ_0002360 depletion worked oppositely. MiR-127-5p, miR-145-5p, miR-585-3p, and miR-758-3p were the targets of circ_0002360, and circ_0002360 could regulate MMP16 expression by competitively binding with the above miRNAs. In summary, circ_0002360 serves as a competitive endogenous RNA to raise MMP16 expressions by competitively binding to miR-127-5p, miR-145-5p, miR-585-3p, and miR-758-3p, thereby promoting NSCLC progression.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Progresión de la Enfermedad , Neoplasias Pulmonares/genética , Metaloproteinasa 16 de la Matriz/genética , MicroARNs/genética , ARN Circular/metabolismo , Regulación hacia Arriba/genética , Secuencia de Bases , Línea Celular Tumoral , Movimiento Celular/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Pulmonares/patología , MicroARNs/metabolismo , Persona de Mediana Edad , Invasividad Neoplásica , ARN Circular/genética
5.
Epidemiol Infect ; 149: e62, 2021 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-33594967

RESUMEN

Coronavirus disease 2019 (COVID-19) is a newly emerged disease with various clinical manifestations and imaging features. The diagnosis of COVID-19 depends on a positive nucleic acid amplification test by real-time reverse transcription-polymerase chain reaction (RT-PCR) for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). However, the clinical manifestations and imaging features of COVID-19 are non-specific, and nucleic acid test for SARS-CoV-2 can have false-negative results. It is presently believed that detection of specific antibodies to SARS-CoV-2 is an effective screening and diagnostic indicator for SARS-CoV-2 infection. Thus, a combination of nucleic acid and specific antibody tests for SARS-CoV-2 will be more effective to diagnose COVID-19, especially to exclude suspected cases.


Asunto(s)
Prueba de COVID-19 , COVID-19/diagnóstico , Neumonía Bacteriana/diagnóstico , SARS-CoV-2/aislamiento & purificación , Adulto , Antibacterianos/uso terapéutico , Anticuerpos Antivirales/sangre , Anticuerpos Antivirales/inmunología , COVID-19/patología , Diagnóstico Diferencial , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/patología , Neumonía Bacteriana/tratamiento farmacológico , Neumonía Bacteriana/patología , ARN Viral/análisis , ARN Viral/genética , SARS-CoV-2/genética , SARS-CoV-2/inmunología , Resultado del Tratamiento , Adulto Joven , Tratamiento Farmacológico de COVID-19
6.
Clin Infect Dis ; 73(11): e4012-e4019, 2021 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-32955081

RESUMEN

BACKGROUND: We aimed to evaluate the efficacy and safety of leflunomide, an approved dihydroorotate dehydrogenase inhibitor, to treat coronavirus disease 2019 (COVID-19) patients with prolonged postsymptomatic viral shedding. METHODS: We conducted a prospective, randomized controlled, open-label trial involving hospitalized adult COVID-19 patients with prolonged polymerase chain reaction (PCR) positivity. Patients were randomly assigned to receive either leflunomide (50 mg every 12 hours, 3 consecutive times, orally; then 20 mg once daily for 8 days), in addition to nebulized interferon alpha 2a (IFN-α-2a, 3 million IU each time, twice daily for 10 days), or nebulized IFN-α-2a alone for 10 days. The primary endpoint was the duration of viral shedding. RESULTS: A total of 50 COVID-19 patients with prolonged PCR positivity were randomized into 2 groups: 26 were assigned to the leflunomide plus IFN-α-2a group, and 24 were assigned to the interferon-alone group. Treatment with leflunomide was not associated with a difference from the interferon-alone group in the duration of viral shedding (hazard ratio for negative reverse-transcription PCR, 0.70 [95% confidence interval, .391-1.256]; P = .186). In addition, the patients given leflunomide did not have a substantially shorter length of hospital stay than patients treated with interferon alone, with median durations of 29.0 (interquartile range [IQR], 19.3-47.3) days and 33.0 (IQR, 29.3-42.8) days, respectively (P = .170). Two leflunomide recipients were unable to complete the full 10-day course of administration due to adverse events. CONCLUSIONS: In COVID-19 patients with prolonged PCR positivity, no benefit in terms of the duration of viral shedding was observed with the combined treatment of leflunomide and IFN-α-2a beyond IFN-α-2a alone.


Asunto(s)
COVID-19 , Adulto , Antivirales/farmacología , Antivirales/uso terapéutico , Dihidroorotato Deshidrogenasa , Humanos , Leflunamida/farmacología , Estudios Prospectivos , SARS-CoV-2 , Resultado del Tratamiento , Esparcimiento de Virus
7.
Infect Dis Poverty ; 9(1): 108, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32746940

RESUMEN

BACKGROUND: The number of coronavirus disease 2019 (COVID-19) cases has rapidly increased all over the world. Specific information about immunity in non-survivors with COVID-19 is scarce. This study aimed to analyse the clinical characteristics and abnormal immunity of the confirmed COVID-19 non-survivors. METHODS: In this single-centered, retrospective, observational study, we enrolled 125 patients with COVID-19 who were died between January 13 and March 4, 2020 in Renmin Hospital of Wuhan University. A total of 414 randomly recruited patients with confirmed COVID-19 who were discharged from the same hospital during the same period served as control. The demographic, clinical characteristics and laboratory findings at admission, and treatment used in these patients were collected. The immunity-related risk factors associated with in-hospital death were tested by logistic regression models and Receiver Operating Characteristic (ROC) curve. RESULTS: Non-survivors (70 years, IQR: 61.5-80) were significantly older than survivors (54 years, IQR: 37-65) (P <  0.001). 56.8% of non-survivors was male. Nearly half of the patients (44.9%) had chronic medical illness. In non-survivors, hypertension (49.6%) was the most common comorbidity, followed by diabetes (20.0%) and coronary heart disease (16.0%). The common signs and symptoms at admission of non-survivors were fever (88%), followed by cough (64.8%), dyspnea (62.4%), fatigue (62.4%) and chest tightness (58.4%). Compared with survivors, non-survivors had higher white blood cell (WBC) count (7.85 vs 5.07 × 109/L), more elevated neutrophil count (6.41 vs 3.08 × 109/L), smaller lymphocyte count (0.69 vs 1.20 × 109/L) and lower platelet count (172 vs 211 × 109/L), raised concentrations of procalcitonin (0.21 vs 0.06 ng/mL) and CRP (70.5 vs 7.2 mg/L) (P < 0.001). This was accompanied with significantly decreased levels of CD3+ T cells (277 vs 814 cells/µl), CD4+ T cells (172 vs 473 cells/µl), CD8+ T cells (84 vs 262.5 cells/µl, P < 0.001), CD19+ T cells (88 vs 141 cells/µl) and CD16+ 56+ T cells (79 vs 128.5 cells/µl) (P < 0.001). The concentrations of immunoglobulins (Ig) G (13.30 vs 11.95 g/L), IgA (2.54 vs 2.21 g/L), and IgE (71.30 vs 42.25 IU/ml) were increased, whereas the levels of complement proteins (C)3 (0.89 vs 0.99 g/L) and C4 (0.22 vs 0.24 g/L) were decreased in non-survivors when compared with survivors (all P < 0.05). The non-survivors presented lower levels of oximetry saturation (90 vs 97%) at rest and lactate (2.40 vs 1.90 mmol/L) (P < 0.001). Old age, comorbidity of malignant tumor, neutrophilia, lymphocytopenia, low CD4+ T cells, decreased C3, and low oximetry saturation were the risk factors of death in patients with confirmed COVID-19. The frequency of CD4+ T cells positively correlated with the numbers of lymphocytes (r = 0.787) and the level of oximetry saturation (r = 0.295), Whereas CD4+ T cells were negatively correlated with age (r =-0.323) and the numbers of neutrophils (r = - 0.244) (all P < 0.001). CONCLUSIONS: Abnormal cellular immunity and humoral immunity were key features of non-survivors with COVID-19. Neutrophilia, lymphocytopenia, low CD4+ T cells, and decreased C3 were immunity-related risk factors predicting mortality of patients with COVID-19.


Asunto(s)
Infecciones por Coronavirus/inmunología , Infecciones por Coronavirus/mortalidad , Neumonía Viral/inmunología , Neumonía Viral/mortalidad , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus/aislamiento & purificación , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , COVID-19 , China/epidemiología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/epidemiología , Femenino , Humanos , Recuento de Leucocitos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Neutrófilos/inmunología , Pandemias , Neumonía Viral/sangre , Neumonía Viral/epidemiología , Curva ROC , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Adulto Joven
8.
Int J Infect Dis ; 99: 219-225, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32758693

RESUMEN

OBJECTIVES: To investigate the proportion and characteristics of asymptomatic infection among healthcare workers (HCWs). METHODS: This study retrospectively investigated 1407 HCWs who were screened for COVID-19 by chest computed tomography (CT) scans and nasopharyngeal swabs for SARS-CoV-2 nucleic acid. Demographics, CT features, nasopharyngeal swabs, baseline symptoms, and laboratory data were collected. RESULTS: Of 1407 HCWs, 235 had symptoms and 1172 were asymptomatic close contacts, of which, 107 were symptomatic cases and 84 were close contacts who had abnormal CT findings. Of 152 symptomatic individuals and 908 close contacts tested for SARS-CoV-2 nucleic acid, 122 symptomatic cases and 38 close contacts had positive reverse-transcriptase real-time polymerase chain (RT-PCR) test results. The rate of confirmed asymptomatic infections was 4.2% (38/908). Both symptomatic and asymptomatic infected cases had high titrations of specific IgG or had ≥four-fold increase in IgG during convalescence compared with the acute phase. Combining the RT-PCR tests and serological findings, the rate of asymptomatic infections was 9.7% (88/908). In terms of the duration of viral shedding, there was no significant difference between symptomatic mild/moderate participants and asymptomatic infections. CONCLUSIONS: The findings demonstrated that a high rate of asymptomatic SARS-CoV-2 carriers existed among healthcare worker close contacts during the outbreak of COVID-19.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Betacoronavirus , Infecciones por Coronavirus/epidemiología , Infecciones por Coronavirus/patología , Personal de Salud , Hospitales de Enseñanza , Neumonía Viral/epidemiología , Neumonía Viral/patología , Adulto , COVID-19 , Portador Sano , China/epidemiología , Infecciones por Coronavirus/diagnóstico , Femenino , Humanos , Masculino , Pandemias , Neumonía Viral/diagnóstico , Estudios Retrospectivos , SARS-CoV-2 , Esparcimiento de Virus , Adulto Joven
9.
Eur J Clin Microbiol Infect Dis ; 39(12): 2279-2287, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32651736

RESUMEN

Recent reports have showed that a proportion of patients with Coronavirus Disease 2019 (COVID-19) presented elevated leukocyte count. Clinical data about these patients is scarce. We aimed to evaluate the clinical findings of patients with COVID-19 who have increased leukocyte at admission. We retrospectively collected the clinical data on the 52 patients who have increased leukocyte count at admission from the 619 patients with confirmed COVID-19 who had pneumonia with abnormal features on chest CT scan in Renmin Hospital of Wuhan University in Wuhan, China, from February 3 to March 3, 2020. The mean age of the 52 patients with increased leukocyte count was 64.7 (SD 11.4) years, 32 (61.5%) were men and 47 (90.4%) had fever. Compared with the patients with non-increased leukocyte count, the patients with increased leukocyte count were significantly older (P < 0.01), were more likely to have underlying chronic diseases (P < 0.01), more likely to develop critically illness (P < 0.01), more likely to admit to an ICU (P < 0.01), more likely to receive mechanical ventilation (P < 0.01), had higher rate of death (P < 0.01) and the blood levels of neutrophil count and the serum concentrations of CRP and IL-6 were significantly increased, (P < 0.01). The older patients with COVID-19 who had underlying chronic disorders are more likely to develop leukocytosis. These patients are more likely to develop critical illness, with a high admission to an ICU and a high mortality rate.


Asunto(s)
Enfermedad Coronaria/diagnóstico , Infecciones por Coronavirus/diagnóstico , Diabetes Mellitus/diagnóstico , Hipertensión/diagnóstico , Leucocitos/patología , Leucocitosis/diagnóstico , Neumonía Viral/diagnóstico , Anciano , Betacoronavirus/patogenicidad , Biomarcadores/sangre , Proteína C-Reactiva/metabolismo , COVID-19 , Prueba de COVID-19 , Técnicas de Laboratorio Clínico , Enfermedad Coronaria/sangre , Enfermedad Coronaria/fisiopatología , Infecciones por Coronavirus/sangre , Infecciones por Coronavirus/mortalidad , Infecciones por Coronavirus/terapia , Enfermedad Crítica , Diabetes Mellitus/sangre , Diabetes Mellitus/fisiopatología , Femenino , Hospitalización/estadística & datos numéricos , Humanos , Hipertensión/sangre , Hipertensión/fisiopatología , Unidades de Cuidados Intensivos , Interleucina-6/sangre , Recuento de Leucocitos , Leucocitos/virología , Leucocitosis/sangre , Leucocitosis/mortalidad , Leucocitosis/terapia , Masculino , Persona de Mediana Edad , Pandemias , Neumonía Viral/sangre , Neumonía Viral/mortalidad , Neumonía Viral/terapia , Respiración Artificial , Estudios Retrospectivos , Factores de Riesgo , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Análisis de Supervivencia
10.
Virol Sin ; 35(6): 725-733, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32696396

RESUMEN

We recently reported that inhibitors against human dihydroorotate dehydrogenase (DHODH) have broad-spectrum antiviral activities including their inhibitory efficacies on SARS-CoV-2 replication in infected cells. However, there are limited data from clinical studies to prove the application of DHODH inhibitors in Coronavirus disease 2019 (COVID-19) patients. In the present study, we evaluated Leflunomide, an approved DHODH inhibitor widely used as a modest immune regulator to treat autoimmune diseases, in treating COVID-19 disease with a small-scale of patients. Cases of 10 laboratory-confirmed COVID-19 patients of moderate type with obvious opacity in the lung were included. Five of the patients were treated with Leflunomide, and another five were treated as blank controls without a placebo. All the patients accepted standard supportive treatment for COVID-19. The patients given Leflunomide had a shorter viral shedding time (median of 5 days) than the controls (median of 11 days, P = 0.046). The patients given Leflunomide also showed a significant reduction in C-reactive protein levels, indicating that immunopathological inflammation was well controlled. No obvious adverse effects were observed in Leflunomide-treated patients, and they all discharged from the hospital faster than controls. This preliminary study on a small-scale compassionate use of Leflunomide provides clues for further understanding of Leflunomide as a potential antiviral drug against COVID-19.


Asunto(s)
Antivirales/administración & dosificación , Tratamiento Farmacológico de COVID-19 , Leflunamida/administración & dosificación , Anciano , Proteína C-Reactiva/metabolismo , COVID-19/diagnóstico por imagen , COVID-19/metabolismo , COVID-19/virología , China , Femenino , Humanos , Pulmón/diagnóstico por imagen , Pulmón/efectos de los fármacos , Masculino , Persona de Mediana Edad , SARS-CoV-2/efectos de los fármacos , SARS-CoV-2/fisiología , Replicación Viral/efectos de los fármacos , Esparcimiento de Virus/efectos de los fármacos
11.
Mol Med Rep ; 12(2): 2511-20, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25936350

RESUMEN

Mesenchymal stem cells (MSCs) have been investigated in the treatment of numerous autoimmune diseases. However, the immune properties of MSCs on the development of asthma have remained to be fully elucidated. Airway dendritic cells (DCs) have an important role in the pathogenesis of allergic asthma, and disrupting their function may be a novel therapeutic approach. The present study used a mouse model of asthma to demonstrate that transplantation of MSCs suppressed features of asthma by targeting the function of lung myeloid DCs. MSCs suppressed the maturation and migration of lung DCs to the mediastinal lymph nodes, and thereby reducing the allergen-specific T helper type 2 (Th2) response in the nodes. In addition, MSC-treated DCs were less potent in activating naive and effector Th2 cells and the capacity of producing chemokine (C-C motif) ligand 17 (CCL17) and CCL22, which are chemokines attracting Th2 cells, to the airways was reduced. These results supported that MSCs may be used as a potential treatment for asthma.


Asunto(s)
Asma/terapia , Células Dendríticas/inmunología , Pulmón/inmunología , Trasplante de Células Madre Mesenquimatosas , Animales , Anticuerpos Neutralizantes/administración & dosificación , Asma/inducido químicamente , Asma/inmunología , Asma/patología , Diferenciación Celular , Movimiento Celular , Quimiocina CCL17/antagonistas & inhibidores , Quimiocina CCL17/biosíntesis , Quimiocina CCL17/inmunología , Quimiocina CCL22/antagonistas & inhibidores , Quimiocina CCL22/biosíntesis , Quimiocina CCL22/inmunología , Células Dendríticas/efectos de los fármacos , Células Dendríticas/patología , Modelos Animales de Enfermedad , Femenino , Humanos , Pulmón/patología , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/patología , Activación de Linfocitos , Células Madre Mesenquimatosas/inmunología , Células Madre Mesenquimatosas/patología , Ratones , Ratones Endogámicos BALB C , Ovalbúmina/administración & dosificación , Células Th2/inmunología , Células Th2/patología
12.
Int J Mol Sci ; 13(5): 6382-6398, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22754371

RESUMEN

In this paper, Fe(3)O(4) nanoparticles (Fe(3)O(4) NPs) grafted carboxyl groups of multiwalled carbon nanotubes with cationic polyelectrolyte poly (dimethyldiallylammonium chloride) (PDDA) (MWCNTs-COO(-)/PDDA@Fe(3)O(4)), are successfully synthesized and used for the extraction of six kinds of major toxic polychorinated biphenyls (PCBs) from a large volume of water solution. The hydrophilicity of the PDDA cage can enhance the dispersibility of sorbents in water samples, and the superparamagnetism of the Fe(3)O(4) NPs facilitate magnetic separation which directly led to the simplification of the extraction procedure. With the magnetic solid-phase extraction (MSPE) technique based on the MWCNTs-COO(-)/PDDA@Fe(3)O(4) sorbents, it requires only 30 min to extract trace levels of PCBs from 500 mL water samples. When the eluate condensed to 1.0 mL, concentration factors for PCBs became over 500. The spiked recoveries of several real water samples for PCBs were in the range of 73.3-98.9% with relative standard deviations varying from 3.8% to 9.4%, reflecting good accuracy of the method. Therefore, preconcentration of trace level of PCBs by using this MWCNTs-COO(-)/PDDA@Fe(3)O(4) sorbent, which are stable for multiple reuses, from water solution can be performed.


Asunto(s)
Óxido Ferrosoférrico/química , Nanopartículas de Magnetita/química , Nanotubos de Carbono/química , Bifenilos Policlorados/química , Polietilenos/química , Compuestos de Amonio Cuaternario/química , Interacciones Hidrofóbicas e Hidrofílicas , Microscopía Electrónica de Transmisión , Nanotubos de Carbono/ultraestructura , Tamaño de la Partícula , Extracción en Fase Sólida , Contaminantes Químicos del Agua/aislamiento & purificación
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...