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6.
Anal Methods ; 16(3): 378-385, 2024 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-38117310

RESUMEN

The pretreatment of samples was vital for enhancing the sensitivity and accuracy of analytical methods. An efficient and sensitive method, based on modified QuEChERS with high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) for the simultaneous determination of the 13 sulfonamides (SAs) in soil, was developed. After extraction by sonication with methanol, the clean-up procedure was achieved using QuEChERS with a primary secondary amine (PSA). The quantification of the 13 SAs was performed by HPLC-MS/MS in electrospray ionization (ESI) and multiple reaction monitoring (MRM) modes. Under optimized conditions, the standard solution exhibited good linearity within the range of 0.01-0.5 µg mL-1. The limits of detection and the limits of quantification of the developed method were 0.007-0.030 µg kg-1 and 0.022-0.101 µg kg-1, respectively. The spiked recoveries for the 13 SAs were in the range of 74.5-111.7% with RSD less than 15%. Furthermore, the developed method was successfully applied for the determination of SAs in real soil samples. The above results showed that the proposed method would be an ideal analytical method for SAs in environmental ecological research.


Asunto(s)
Sulfonamidas , Espectrometría de Masas en Tándem , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Sulfonamidas/análisis , Suelo , Cromatografía Líquida con Espectrometría de Masas , Sulfanilamida/análisis
7.
Biomed Res Int ; 2022: 7250127, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35860803

RESUMEN

Background: CLK2 is a splicing regulator and expressed ubiquitously in various malignancies. The study is aimed at exploring the potential roles of CLK2 in the development of colorectal cancer (CRC). Methods: Real-time PCR and analyses of The Cancer Genome Atlas (TCGA) and Human Protein Atlas (HPA) database were utilized to evaluate the CLK2 gene transcription level and protein level of colorectal cancer (CRC) tissue. The chi-squared and logistic regression tests were used to evaluate the relationship between CLK2 and clinicopathologic features. Kaplan-Meier survival curve and Cox regression analysis were performed to explore the prognostic significance of CLK2. The association between CLK2 expression and immune landscapes was explored by CIBERSORT and ESTIMATE. Furthermore, GSEA (Gene Set Enrichment Analysis) and alternative splicing (AS) analyses were performed to investigate the relationship between CLK2 expression and downstream signaling pathway. Results: The CLK2 expression was upregulated in CRC in both transcript and protein level. The elevated expression of CLK2 was correlated with local invasion and poor prognosis. Furthermore, CLK2 induced tumor cell adhesion and thereby promotes local invasion of CRC. The CLK2 expression significantly inhibited plasma cells and eosinophil infiltration and showed no relationship with immune and stromal scores of CRC samples. CLK2 might involve in Notch signaling pathway by regulating the AS of CTBP1. Conclusions: CLK2 might be a potential prognostic biomarker and therapeutic target for colorectal cancer.


Asunto(s)
Neoplasias Colorrectales , Regulación Neoplásica de la Expresión Génica , Biomarcadores , Neoplasias Colorrectales/patología , Humanos , Estimación de Kaplan-Meier , Pronóstico
8.
Bioengineered ; 12(2): 9779-9789, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34696672

RESUMEN

Gastric cancer (GC) is one of the most common and lethal cancers worldwide. The Nudix hydroxylase (NUDT) genes have been reported to play notable roles in tumor progression. However, the role of NUDT10 in GC has not been reported. In this study, we investigated the expression of NUDT10 in GC and its association with clinicopathological characteristics. Quantitative real-time polymerase chain reaction and analyses of The Cancer Genome Atlas and Human Protein Atlas databases were performed to determine NUDT10 mRNA and protein expression. Receiver operating characteristic curve analysis was used to assess the diagnostic value of NUDT10 in patients with GC. We used Cox regression and the Kaplan-Meier method to assess the correlations between clinicopathological factors and survival outcomes of patients with GC. Gene set enrichment analysis (GSEA) was performed to identify the underlying signaling pathways. NUDT10 mRNA and protein expression was significantly lower in GC tissues compared to normal tissues. Interestingly, higher NUDT10 expression was correlated with advanced tumor stage, deeper local invasion, and worse survival outcomes. Patients with higher NUDT10 expression had a significantly worse prognosis than those with lower NUDT10 expression. Multivariate analysis showed that high NUDT10 expression was an independent predictor of survival outcome. Several pathways, including mismatch repair, nucleotide excision repair, extracellular matrix receptor interaction, and cancer signaling, were identified as enriched pathways in GC through GSEA. To our knowledge, this study is the first to characterize NUDT10 expression in GC. Our study demonstrates that NUDT10 is a promising independent biomarker for GC prognosis.


Asunto(s)
Biomarcadores de Tumor/biosíntesis , Bases de Datos de Ácidos Nucleicos , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Proteínas de Neoplasias/biosíntesis , Pirofosfatasas/biosíntesis , Neoplasias Gástricas/enzimología , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proteínas de Neoplasias/genética , Pronóstico , Pirofosfatasas/genética , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/genética
9.
Gastroenterol Res Pract ; 2020: 8437250, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33335548

RESUMEN

BACKGROUND AND AIMS: Circular RNA (circRNA) demonstrates potential biological application in various solid tumors. We intended to evaluate the diagnostic, prognostic, and clinicopathological value of circRNA for esophageal cancer (EC). METHODS: We screened relative studies from Pubmed, Embase, Web of Science, and Cochrane Library. The diagnostic role of circRNAs was testified by pooled sensitivity and specificity. Pooled odds ratio (OR) and pooled hazard ratio (HR) were computed to appraise the clinicopathological and prognostic value, respectively. RESULTS: There were total 15 articles suitable with our included criteria, in which 7 for diagnosis, 8 for prognosis, and 9 for clinicopathological features. The pooled sensitivity and specificity were 0.77 and 0.80, respectively, while the AUC was 0.85. Patients with aberrant expression of circRNAs had a 2.92-fold increased risk of developing EC. The proportion of EC patients with normal circRNA expression only accounted for 29%. Upregulated expression of oncogenic circRNA was correlated with poor clinicopathological features, including lymph node metastasis, tumor size, and T classification, while downregulation of tumor-suppressor circRNA was contributed to worse TNM stage. As for prognosis, upregulated expression of circRNA carried out a diverse survival outcome, with a pooled HR of 2.76 for tumor promoter and that of 0.21 for tumor suppressor. High expression of oncogenic circRNA in both plasma and tumor tissue would lead to a shorter survival duration. CONCLUSION: circRNAs might be a promising biomarker for diagnosis, prognosis, and clinicopathological features of EC.

10.
Biomed Res Int ; 2020: 6909672, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33083477

RESUMEN

BACKGROUND: Inhibin subunit beta B (INHBB) is a protein-coding gene that participated in the synthesis of the transforming growth factor-ß (TGF-ß) family members. The study is aimed at exploring the clinical significance of INHBB in patients with colorectal cancer (CRC) by bioinformatics analysis. METHODS: Real-time PCR and analyses of Oncomine, Gene Expression Omnibus (GEO), and The Cancer Genome Atlas (TCGA) databases were utilized to evaluate the INHBB gene transcription level of colorectal cancer (CRC) tissue. We evaluated the INHBB methylation level and the relationship between expression and methylation levels of CpG islands in CRC tissue. The corresponding clinical data were obtained to further explore the association of INHBB with clinical and survival features. In addition, Gene Set Enrichment Analysis (GSEA) was performed to explore the gene ontology and signaling pathways of INHBB involved. RESULTS: INHBB expression was elevated in CRC tissue. Although the promoter of INHBB was hypermethylated in CRC, methylation did not ultimately correlate with the expression of INHBB. Overexpression of INHBB was significantly and positively associated with invasion depth, distant metastasis, and TNM stage. Cox regression analyses and Kaplan-Meier survival analysis indicated that high expression of INHBB was correlated with worse overall survival (OS) and disease-free survival (DFS). GSEA showed that INHBB was closely correlated with 5 cancer-promoting signaling pathways including the Hedgehog signaling pathway, ECM receptor interaction, TGF-ß signaling pathway, focal adhesion, and pathway in cancer. INHBB expression significantly promoted macrophage infiltration and inhibited memory T cell, mast cell, and dendritic cell infiltration. INHBB expression was positively correlated with stromal and immune scores of CRC samples. CONCLUSION: INHBB might be a potential prognostic biomarker and a novel therapeutic target for CRC.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Subunidades beta de Inhibinas/genética , Anciano , Neoplasias Colorrectales/inmunología , Neoplasias Colorrectales/patología , Islas de CpG , Metilación de ADN , Femenino , Regulación Neoplásica de la Expresión Génica , Ontología de Genes , Proteínas Hedgehog/genética , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Pronóstico , Regiones Promotoras Genéticas , Modelos de Riesgos Proporcionales , Transducción de Señal/genética , Transducción de Señal/inmunología , Factor de Crecimiento Transformador beta/genética
11.
Int J Mol Med ; 46(1): 397-405, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32626915

RESUMEN

The aberrant expression of microRNA (miRNAor miR)­383­5p has been found in numerous types of cancer. However, the function of miR­383­5p in gastric cancer (GC) remains elusive and requires further investigation. In the present study, the level of miR­383­5p and cancerous inhibitor of PP2A (CIP2A) in GC cell lines was determined by reverse transcription­quantitative PCR analysis. GC cell proliferation, apoptosis and cell cycle distribution were determined by the MTT assay and flow cytometry, respectively. The mRNA target of miR­383­5p was identified by dual luciferase activity assay. It was observed that the expression of miR­383­5p was lower and that of CIP2A was higher in GC cells compared with the GES­1 normal human gastric epithelial cell line. Transfectoin with miR­383­5p mimic significantly inhibited GC cell proliferation, while it promoted cell apoptosis and G0/G1 arrest by targeting CIP2A. Taken together, the findings of the present study demonstrate that miR­383­5p inhibits GC cell proliferation and promotes apoptosis and G0/G1 arrest by targeting CIP2A, indicating that targeting miR­383­5p may hold promise as a future therapeutic strategy for patients with GC.


Asunto(s)
MicroARNs/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patología , Apoptosis/genética , Apoptosis/fisiología , Western Blotting , Ciclo Celular/genética , Ciclo Celular/fisiología , Línea Celular , Proliferación Celular/genética , Proliferación Celular/fisiología , Regulación Neoplásica de la Expresión Génica/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Células HEK293 , Humanos , MicroARNs/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transducción de Señal/genética , Transducción de Señal/fisiología , Neoplasias Gástricas/genética
12.
BMC Cancer ; 20(1): 448, 2020 May 19.
Artículo en Inglés | MEDLINE | ID: mdl-32429931

RESUMEN

BACKGROUND: Circular RNAs (circRNAs) are research hotspots in the network of noncoding RNAs in numerous tumours. The purpose of our study was to evaluate the clinicopathological, prognostic and diagnostic value of circRNAs in colorectal cancer. METHODS: The PubMed, Cochrane Library, and Web of Science online databases were searched for relevant studies before May 15, 2019. Pooled hazard ratios (HRs) and odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the association between circRNAs expression, and overall survival (OS) and clinical parameters. Pooled sensitivity, specificity, and the area under the curve (AUC) were employed to assess the diagnostic value of circRNAs. RESULTS: A total of 19 studies were enrolled in this meta-analysis, with 11 on clinicopathological parameters, 8 on prognosis and 7 on diagnosis. For clinicopathological and prognostic value, elevated expression of oncogenic circRNAs was correlated with poor clinical parameters (tumor size: OR = 1.769, 95% CI: 1.097-2.852; differentiation grade: OR = 1.743, 95% CI: 1.032-2.946; TNM stage: OR = 3.320, 95% CI: 1.529-7.207; T classification: OR = 3.410, 95% CI: 2.088-5.567; lymph node metastasis: OR = 3.357, 95% CI: 2.160-5.215; distal metastasis: OR = 4.338, 95% CI: 2.503-7.520) and worse prognosis (HR = 2.29, 95% CI: 1.50-3.52). However, elevated expression of tumor-suppressor circRNAs was correlated with better clinical parameters (differentiation grade: OR = 0.453, 95% CI: 0.261-0.787; T classification: OR = 0.553, 95% CI: 0.328-0.934; distal metastasis: OR = 0.196, 95% CI: 0.077-0.498) and favorable prognosis (HR = 0.37, 95% CI: 0.22-0.64). For diagnostic value, the pooled sensitivity, specificity, and AUC were 0.82 (95% CI, 0.75-0.88), 0.72 (95% CI, 0.66-0.78), and 0.82 (95% CI, 0.78-0.85), respectively. CONCLUSIONS: These results indicate that circRNAs may be potential biomarkers for the diagnosis and prognosis of colorectal cancer.


Asunto(s)
Biomarcadores de Tumor/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , ARN Circular/genética , Humanos , Pronóstico
13.
J Clin Lab Anal ; 34(8): e23341, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32309888

RESUMEN

BACKGROUND: Cancer has become a public health problem with high morbidity and mortality. Recent publications have shown that exosomes can be used as potential diagnostic biomarkers of cancer. However, the diagnostic accuracy and reliability of circulating exosomes remain unclear. The present meta-analysis was conducted to comprehensively summarize the overall diagnostic performance of circulating exosomes for cancer. METHODS: Eligible studies published up to June 27, 2019, on PubMed, Embase, and Cochrane Library were selected for the meta-analysis. All statistical analyses were performed by STATA 15.1 statistical software and Meta-DiSc 1.4. Quality Assessment for Studies of Diagnostic Accuracy 2 tool was used to access the quality of included studies. A bivariate mixed-effects model was applied to calculate the diagnostic indexes from included studies. RESULTS: A total of 5924 participants comprising 3161 cases and 2763 controls from 42 eligible studies were analyzed. The pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the area under the curve with 95% confidence intervals (95% CI) were as follows: 0.79 (0.75-0.82), 0.81 (0.78-0.84), 4.1 (3.5-4.8), 0.26 (0.22-0.31), 16 (12-21), and 0.87 (0.84-0.89), respectively. Sensitivity analysis suggested no study exclusively contributed to the heterogeneity, and Deeks' funnel plot asymmetry test indicated no potential publication bias (P = .09). CONCLUSIONS: The meta-analysis indicated that circulating exosomes could serve as effective and minimally invasive biomarkers for diagnosis of cancer, especially in patients with hepatocellular carcinoma or ovarian cancer, serum-based samples and exosomal proteins.


Asunto(s)
Biomarcadores de Tumor/sangre , Exosomas , Neoplasias , Humanos , Neoplasias/sangre , Neoplasias/diagnóstico
14.
Artículo en Inglés | MEDLINE | ID: mdl-24060595

RESUMEN

A method was established for the determination of three phenolic environmental estrogens, namely bisphenol A (BPA), nonylphenol (NP) and octylphenol (OP), in urine from women of uterine leiomyoma group (n=49) and control group (n=29), by using solid-phase extraction (SPE) coupled with liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). Urine samples were spiked with 2,4,6-tribromophenyl-terminated tetrabromobisphenol-A carbonate oligomer (TBBPA) and nonylphenol D8 (NP-D8) as internal standard (I.S.) and de-conjugated by adding ß-glucuronidase and sulfatase before the SPE. The extraction recoveries of BPA, NP and OP were more than 73.3%; the standard curve was linear over the validated concentrations in the range of 1.0-100.0ng/mL and the limits of detection (LOD) of BPA, NP and OP were 0.32ng/mL, 0.18ng/mL and 0.15ng/mL, respectively. Moreover, by analysing quality control urine samples in 5 days, the results showed that the method was precise and accurate, for the intra- and inter-day CV% within 15.2%. Except that OP was not found (3). NP levels were significantly higher in uterine leiomyoma patients than control group in low gravidity subgroup. Though BPA levels in experimental and control groups were not significantly different, the mean levels and concentration distribution were different. The study suggested that there is certain relationship between exposure concentrations of phenolic environmental estrogens and uterine leiomyoma disease.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Estrógenos no Esteroides/orina , Leiomioma/orina , Fenoles/orina , Espectrometría de Masas en Tándem/métodos , Neoplasias Uterinas/orina , Adulto , Estudios de Casos y Controles , Estabilidad de Medicamentos , Estrógenos no Esteroides/envenenamiento , Femenino , Humanos , Leiomioma/inducido químicamente , Límite de Detección , Modelos Lineales , Persona de Mediana Edad , Reproducibilidad de los Resultados , Extracción en Fase Sólida , Neoplasias Uterinas/inducido químicamente
15.
Anal Chim Acta ; 769: 65-71, 2013 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-23498122

RESUMEN

In this paper, bamboo charcoals were modified using Fe3O4 nanosheets for the first time. The composites, as a novel solid-phase microextraction (SPME) fiber coating, were used for the extraction of seven polybrominated diphenyl ethers (PBDEs) in environmental water samples. The extraction factors (stirring rate, extraction time, and ionic strength) and desorption factors (desorption time and desorption temperature) of the fibers were systematically investigated and optimized. Under optimum conditions, the linear range was 1-1000 ng L(-1). Based on the ratio of chromatographic signal to base line noise (SN(-1)=3), the limits of detection (LODs) can reach 0.25-0.62 ng L(-1). The novel method was successful in the analysis of PBDEs in real environmental water samples. The results indicate that bamboo charcoal/Fe3O4 as an SPME coating material coupled with gas chromatography-negative chemical ionization-mass spectrometry is an excellent method for the routine analysis of PBDEs at trace levels in environmental water samples.


Asunto(s)
Carbón Orgánico/química , Óxido Ferrosoférrico/química , Cromatografía de Gases y Espectrometría de Masas , Éteres Difenilos Halogenados/análisis , Contaminantes Químicos del Agua/análisis , Adsorción , Bambusa/química , Éteres Difenilos Halogenados/aislamiento & purificación , Microextracción en Fase Sólida , Contaminantes Químicos del Agua/aislamiento & purificación
16.
Anal Bioanal Chem ; 391(8): 2915-21, 2008 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-18587565

RESUMEN

This paper describes a novel, simple and environmentally friendly method for rapid determination of the amide herbicides metoalchlor, acetochlor, and butachlor. It is based on dispersive liquid-liquid microextraction and gas chromatography-mass spectrometry. Factors that may influence the enrichment efficiency, such as type and volume of extraction solvent, type and volume of dispersive solvent, extraction time, and content of NaCl, were investigated and optimized in detail. Under the optimum conditions, the limits of detection of metoalchlor, acetochlor, and butachlor were 0.02, 0.04, and 0.003 microg L(-1), respectively. The experimental results indicated that there was linearity over the range 0.1-50 microg L(-1) and good reproducibility with relative standard deviations over the range 1.6-3.0% (n = 5). The proposed method has been applied for the analysis of real-world water samples, and satisfactory results were achieved. Average recoveries of spiked herbicides were in the range 80.3-108.8%. All of these indicated that the developed method would be an efficient method for simultaneous determination of the three herbicides in environmental water samples.

17.
Anal Bioanal Chem ; 387(8): 2911-5, 2007 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-17377785

RESUMEN

Hollow-fiber liquid-phase microextraction (HF-LPME), a relatively new sample preparation technique, has attracted much interest in the field of environmental analysis. In the current study, a novel method based on hollow-fiber liquid-phase microextraction with in situ derivatization and gas chromatography-mass spectrometry for the measurement of triclosan in aqueous samples is described. Hollow-fiber liquid-phase microextraction conditions such as the type of extraction solvent, the stirring rate, the volume of derivatizing reagent, and the extraction time were investigated. When the conditions had been optimized, the linear range was found to be 0.05-100 microg l(-1) for triclosan, and the limit of detection to be 0.02 microg l(-1). Tap water and surface water samples collected from our laboratory and Wohushan reservoir, respectively, were successfully analyzed using the proposed method. The recoveries from the spiked water samples were 83.6 and 114.1%, respectively; and the relative standard deviation (RSD) at the 1.0 microg l(-1) level was 6.9%.


Asunto(s)
Antiinfecciosos Locales/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Triclosán/análisis , Contaminantes Químicos del Agua/análisis , Sensibilidad y Especificidad
18.
Anal Bioanal Chem ; 387(2): 687-94, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17139487

RESUMEN

A novel purge-and-trap method coupled with gas chromatography-mass spectrometry (GC-MS) is developed for the analysis of trace and ultratrace phenols based on their derivatization with acetic anhydride. Parameters affecting the extraction efficiency, such as purge temperature, concentration of sodium chloride, purge time, and volume of derivatization reagent, were investigated. The optimized conditions were addition of 150 microL acetic anhydride, purge time of 25 min at the purge temperature of 60 degrees C with 30% NaCl. The linear range was 0.2-100 microg L(-1) for phenols. The limits of detection (LODs) ranged from 0.08 to 0.15 microg L(-1) and the relative standard deviations (RSDs) for most of the phenols at the 10 microg L(-1) level were below 10%. Natural water samples collected from a pool were successfully analyzed using the proposed method. The recovery of spiked water samples was 72.9-84.2%.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Fenoles/análisis , Contaminantes del Agua/análisis , Acetilación , Cromatografía de Gases y Espectrometría de Masas/normas , Métodos , Estándares de Referencia , Sensibilidad y Especificidad
19.
Anal Bioanal Chem ; 385(6): 1082-6, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16770579

RESUMEN

This paper demonstrates headspace liquid-phase microextraction (HS-LPME) as used for the determination of volatile residual solvents in pharmaceutical products. This method is based on headspace liquid-phase microextraction capillary column gas chromatography. Under optimum conditions, the linerary of the method ranged from 1 to 1,000 mg l(-1). The limits of detection are 0.2-6.0 [corrected] mg l(-1) and relative standard deviations (RSD) for most of the volatile solvents were below 10%. This novel method is applied to the analysis of volatile residual solvents in pharmaceutical products with satisfactory results.


Asunto(s)
Cromatografía de Gases/métodos , Contaminación de Medicamentos , Ionización de Llama/métodos , Preparaciones Farmacéuticas/análisis , Solventes/análisis , Cromatografía de Gases/normas , Ionización de Llama/normas , Microquímica/métodos , Reproducibilidad de los Resultados , Volatilización
20.
Anal Sci ; 22(4): 563-6, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16760598

RESUMEN

In this paper, a novel method for the determination of chloroform in drinking water has been described. It is based on liquid-phase microextraction (LPME) and gas chromatography-mass spectrometry (GC-MS). Extraction conditions such as solvent selection, organic solvent dropsize, stirring rate, content of NaCl and extraction time were found to have significant influence on extraction efficiency. The optimized conditions were 1.5 microl xylene, 20 min extraction time at 400 rpm stirring rate without NaCl addition. The linear range was 1.0 - 100 microg l(-1) for chloroform. The limit of detection (LOD) was 1.0 microg l(-1); and relative standard deviation (RSD) at the 30 microg l(-1) level was 2.9%. Tap water samples from a laboratory were successfully analyzed using the proposed method. The relative recovery of spiked water samples was 104%.


Asunto(s)
Cloroformo/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Contaminantes del Agua/análisis , Algoritmos , Concentración Osmolar , Reproducibilidad de los Resultados , Cloruro de Sodio/química , Agua/química , Xilenos/química
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