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1.
Artigo em Inglês | MEDLINE | ID: mdl-38971075

RESUMO

Peganum harmala L., a traditional medicinal plant in China, is renowned for its significant alkaloid content in seeds and roots exhibiting a wide range of pharmacological activities, including antidepressant, antiseptic, and antiviral. However, the volatile composition of the herb remained unclear. Apart from that, the extraction of volatile compounds through essential oil presents challenges due to the low yield and the degradation of volatile active compounds at high temperatures. This study used multiple sample preparation methods including headspace (HS), needle trap device (NTD), and liquid-liquid extraction (LLE) coupled with gas chromatography-mass spectrometry (GC-MS) to analyze the volatile compounds from the areal part of P. harmala L.. A total of 93 compounds were identified with NTD facilitating the first detection of harmine among the volatile organic compounds. Through network pharmacology and protein interaction analysis, the compounds' potential therapeutic targets of the compounds were explored, and 23 key targets were obtained (AKT1, ALB, PTGS2, MAOA, etc). KEGG pathway enrichment analysis indicated significant involvement in neuroactive ligand-receptor interactions and serotonergic synapses. The results enhanced the understanding of P. harmala's pharmacological mechanisms and supported its ethnopharmacological use.


Assuntos
Antidepressivos , Cromatografia Gasosa-Espectrometria de Massas , Peganum , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Peganum/química , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Antidepressivos/análise , Antidepressivos/química , Antidepressivos/farmacologia , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Óleos Voláteis/química , Óleos Voláteis/análise , Extração Líquido-Líquido/métodos , Humanos , Mapas de Interação de Proteínas
2.
Talanta ; 276: 126255, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38776771

RESUMO

Needle Trap Device (NTD) as a novel, versatile, and eco-friendly technique has played an important role in analytical and environmental chemistry. The distinctive role of this interdisciplinary technique can be defended through the sampling and analysis of biological samples and industrial pollutants in gaseous and liquid environments. In recent years, significant efforts have been made to enhance the performance of the needle trap device resulting in the development of novel extraction routes by various packing materials with improved selectivity and enhanced adsorption characteristics. These achievements can lead to the facilitated pre-concentration of desired analytes. This review tries to have a comparative and comprehensive survey of the three important areas of NTD technique: I) Fabrication and preparation procedures of NTDs; II) Sampling techniques of pollutants using NTDs; and III) Employed materials as adsorbents in NTDs. In the packing-material section, the commercial and synthetic adsorbents such as carbon materials, metal-organic frameworks, aerogel, and polymers are considered. Furthermore, the limitations and potential areas for future development of the NTD technique are presented.


Assuntos
Agulhas , Adsorção , Poluentes Ambientais/análise , Estruturas Metalorgânicas/química
3.
Chemosphere ; 277: 130251, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33774250

RESUMO

Volatile Organic Compounds (VOCs) are a large group of chemicals mostly found in indoor environments such as homes and workplaces. Long term exposure to certain VOCs can cause symptoms in some individuals and therefore, monitoring and controlling air quality can help better manage chronic respiratory diseases. In this study, we aimed to develop an easy-to-use, economical, in house needle trap-based methodology to detect certain VOCs to be used for public and occupational health. For this purpose, a multi-bed (packed with PDMS/Carbopack-X/Carboxen-1000) needle trap device (NTD) was utilized for sampling, enrichment, and injection of the VOCs into the gas chromatography. The performance of the developed method was investigated for the analysis of the group known as BTEX (benzene, toluene, ethylbenzene and xylene). Operational and instrumental parameters such as sampling flow rate and relative humidity, desorption time and temperature were optimized, and the analytical figures of merit of the proposed method have indicated that very low levels of BTEX in air samples can be easily determined by this new method. Overall results have shown that multi-bed NTD offers a high sensitive procedure for sampling and analysis of BTEX in concentration range of 0.002-0.298 mg/m3 in indoor air.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Benzeno/análise , Monitoramento Ambiental , Humanos , Tolueno/análise , Compostos Orgânicos Voláteis/análise , Xilenos/análise
4.
Anal Sci ; 37(1): 159-165, 2021 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-33342926

RESUMO

In this review, we summarize the methods of sample introduction into a gas chromatograph. For volatile organic compounds, headspace measurements and purge-trap methods have been used traditionally. Recently, the trapped headspace method has been used in water quality testing. In addition, various solid-state adsorption methods have been developed, including a method in which the adsorbent is placed inside a needle, while new adsorbents and their applications have also been introduced.

5.
Chemosphere ; 250: 126284, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32234620

RESUMO

Semi-volatile organic compounds (SVOCs), such as phthalates, organophosphates, and polybrominated diphenyl ethers, are emerging as an important class of pollutants that are of serious health concerns. Determining concentrations of these pollutants is of great importance for environmental and exposure studies. In this work, a needle trap device (NTD) method was developed to measure the concentration of SVOCs in air samples. Sorbents were packed in the NTD to capture SVOCs with the aid of a sampling pump. NTD operational parameters, such as desorption temperature, desorption time, and sampling flow rate, were optimized for the target SVOCs. The limit of detection for air sampling by the NTD method ranged between 5 pg and 1 ng, depending on the SVOC compound. The variations in terms of NTD repeatability and reproducibility were lower than 14% for all cases. In addition, the influence of other experimental parameters, such as sampling temperature and humidity, breakthrough volume, NTD storage time, as well as carryover effect were examined. Finally, NTDs were used to determine emissions of gas-phase SVOCs from various consumer products in an emission cell and to collect total airborne SVOC samples (gas and particle phases) in an office. The results of NTD method were in an agreement with data obtained by conventional active sampling methods using Tenax® sorbent tubes and polyurethane foam samplers, but with improvements of relative standard deviation, sensitivity, and sampling time. The results demonstrated that the NTD method is a simple, sensitive, effective, reusable, and inexpensive technique for sampling and analyzing SVOCs in the concentration range from 2 ng m-3 to 100 µg m-3 in air.


Assuntos
Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Agulhas , Compostos Orgânicos Voláteis/análise , Alcanos/análise , Monitoramento Ambiental/instrumentação , Desenho de Equipamento , Éteres Difenil Halogenados/análise , Ácidos Ftálicos/análise , Temperatura
6.
Biomed Chromatogr ; 34(4): e4800, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31994204

RESUMO

The aim of this study was to develop a new method for the determination of benzene, toluene, ethylbenzene and xylene isomers (BTEXs) in urine samples. In this method, MIL-100(Fe)@Fe3 O4 @SiO2 metal-organic framework was synthesized, characterized and packed inside a needle trap device (NTD) as a sorbent for headspace extraction of unmetabolized BTEXs from urine samples followed by gas chromatography (GC) analysis. The GC device was equipped with a flame ionization detector (FID). The results showed that the optimal extraction time, extraction temperature and salt content were 60 min, 30°C and 5%, respectively. Also, the optimal desorption time and temperature were determined to be 1 min and 250°C, respectively. The limits of detection and quantification of the analytes of interest were in the ranges 0.0001-0.0005 and 0.0003-0.0014 µg ml-1 , respectively. The intra- and inter-day repeatability were <7.6%. The accuracy of the measurements in urine samples was in the range 7.1-11.4%. The results also demonstrated that the proposed NTD offered various advantages such as having high sensitivity and being inexpensive, reusable, user friendly, environmentally friendly and compatible for use with the GC device. Therefore, it can be efficiently used as a MIL-NTD for the extraction and analysis of unmetabolized BTEXs from urine samples.


Assuntos
Derivados de Benzeno/isolamento & purificação , Derivados de Benzeno/urina , Ferro/química , Estruturas Metalorgânicas/química , Exposição Ambiental/análise , Desenho de Equipamento , Humanos , Limite de Detecção , Modelos Lineares , Agulhas , Reprodutibilidade dos Testes , Dióxido de Silício/química
7.
Anal Chim Acta ; 1083: 119-129, 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31493802

RESUMO

Polyaniline silica (Silica/PANI) organic-inorganic nanocomposite was synthesized by combining electrospinning and in-situ polymerization processes. This strategy prevented the aggregation of PANI during the polymerization and led to higher synthesis's yield and more uniformity of the produced composite. The structure and morphology of the nanocomposite was characterized using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), and X-ray diffraction (XRD) techniques. The prepared nanocomposite was then packed inside a stain-steel needle and evaluated as a needle trap device (NTD), for simultaneous headspace extraction of polycyclic aromatic hydrocarbons (PAHs) and benzene, toluene, ethylbenzene, and xylenes (BTEX) in polluted soil samples, before GC-FID analysis, as a low-cost and robust detector. Response surface methodology (RSM) involving Box-Behnken design (BBD) was implemented to evaluate the effective experimental variables and subsequent introduction of a multiple function to describe the experimental conditions for the extraction of the analytes. Wide calibration plots (1-2000 ng g-1 for BTEX and 0.2-2000 ng g-1 for PAHs) with acceptable linearity (R2 > 0.99) were obtained under the optimal conditions. The limits of detection were found to be 0.02-0.1 ng g-1for BTEX and 0.001-0.01 ng g-1 for PAHs. The calculated standard deviations were 7.3-13.2% (n = 6). The developed NTD-GC-FID method was successfully applied for the extraction and determination of PAHs and BTEX in contaminated soil samples.

8.
J Chromatogr A ; 1602: 74-82, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31176481

RESUMO

The purpose of this study was to develop a new method for the sampling and analysis of naphthalene (Nap) and phenanthrene (Phe) in air. XAD-2 sorbent was prepared with polyaniline (PANI) to increase its adsorption area. Thus, 22-gauge needles were packed with XAD-2/PANI sorbent for the extraction of Nap and Phe, and sampling of the analytes of interest. The compounds were dynamically sampled from the headspace of the flask in laboratory and then analyzed using a gas chromatography (GC) device equipped with flame ionization detector (FID). The needle trap device (NTD) with the proposed sorbent was more sensitive and accurate than the NIOSH 5515 method. The results showed that the optimal temperature and time for the desorption of the analytes were 350 °C and 8 min, respectively. The analytical parameters such as carryover effect, breakthrough volume, and storage time were examined. The repeatability of the method was determined to be 9.4-13.5% for Nap and 7.1-15.7% for Phe. The limits of detection (LOD) for the analytes were in the range 0.002 - 0.09 ng L-1, and the limits of quantitation (LOQ) were in the range 0.01- 0.23 ng L-1. It was also found that the NTD packed with XAD-2/PANI sorbent was a sensitive and cost-effective method, and offered a high accuracy for the sampling and analysis of PAHs in air.


Assuntos
Poluentes Atmosféricos/análise , Compostos de Anilina/química , Técnicas de Química Analítica/instrumentação , Naftalenos/análise , Fenantrenos/análise , Adsorção , Poluentes Atmosféricos/isolamento & purificação , Cromatografia Gasosa , Ionização de Chama , Limite de Detecção , Agulhas , Hidrocarbonetos Policíclicos Aromáticos/análise , Temperatura
9.
J Environ Health Sci Eng ; 17(2): 1045-1053, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32030173

RESUMO

BACKGROUND: A needle trap device (NTD) was packed with Carbotrap/silica composite sorbent and applied for field sampling of halogenated volatile organic compounds (HVOCs) followed by gas chromatography/mass spectrometry (GC/MS) separation and determination. METHODS: Carbotrap B, as a highly pure surface sorbent, was prepared using sol-gel method to improve its surface properties for adsorption/desorption of the target analytes. The effects of important experimental variables on the sampling and determination of trichloroethylene (thrCE) and tetrachloroethylene (tetCE) using the proposed NTD-GC/MS strategy were evaluated and optimized. RESULTS: The results showed that sampling temperature and relative humidity interfered with sampling efficiency of the developed method and peak area responses of the analytes decreased with increasing temperature and relative humidity. The peak areas of the analytes increased with raising desorption temperature from 180 to 250 °C, and increasing desorption time from 1 to 3 min. The carryover experiments showed that the carryover effect disappeared after 3 min of desorption time. The Limits of Detection (LODs) and Limits of Quantitation (LOQs) of the analytes were in the range 0.01-0.03 and 0.05-0.09, respectively. CONCLUSIONS: The results indicated that the developed NTD-GC/MS procedure can be used as a technology with high sensitivity for the field sampling and determination of HVOCs.

10.
R Soc Open Sci ; 5(6): 171987, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30110475

RESUMO

To characterize the chemical differences of volatile components between crude and processed Baizhu Shaoyao San (BSS), a classical Chinese herbal formula that is widely applied in the treatment of gastrointestinal diseases, we developed a gas chromatography-mass spectrometry-based needle trap device combined with multivariate data analysis to globally profile volatile components and rapidly identify differentiating chemical markers. Using a triple-bed needle packed with Carbopack X, DVB and Carboxen 1000 sorbents, we identified 121 and 123 compounds, respectively, in crude and processed BSS. According to the results of principal component analysis and orthogonal partial least-squares discriminant analysis, crude and processed BSS were successfully distinguished into two groups with good fitting and predicting parameters. Furthermore, 21 compounds were identified and adopted as potential markers that could be employed to quickly differentiate these two types of samples using S-PLOT and variable importance in projection analyses. The established method can be applied to explain the chemical transformation of Chinese medicine processing in BSS and further control the quality and understand the processing mechanism of Chinese herbal formulae. Besides, the triple-bed needle selected and optimized in this study can provide a valuable reference for other plant researches with similar components. Furthermore, the systematic research on compound identification and marker discrimination of the complex components in crude and processed BSS could work as an example for other similar studies, such as composition changes in one plant during different growth periods, botanical characters of different medicinal parts in same kind of medicinal herbs and quality identification of one species of medicinal herb from different regions.

11.
J Chromatogr A ; 1565: 1-18, 2018 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-29937120

RESUMO

Microextraction techniques are widely applied for sample preparation to gas chromatographic analysis of target compounds in samples with a complex matrix. Recently, needle-based microextraction techniques have been developed in order to improve performance of the extraction. The main advantages of these techniques are miniaturization, automation, high performance, environmentally friendliness and on-line coupling with analytical instruments. This review focuses on the three needle-based microextraction techniques including solid-phase dynamic extraction (SPDE), in-tube extraction (ITEX) and needle trap device extraction (NTD). The core of the aforementioned techniques is an extraction phase protected in the stainless steel needle. The application of the sorbent-protected needle extraction techniques for the gas chromatographic analysis of environmental, biological and food samples is discussed. The fundamental aspects and development over the years are also summarized.


Assuntos
Cromatografia Gasosa/métodos , Agulhas , Microextração em Fase Sólida/métodos , Adsorção , Cromatografia Gasosa-Espectrometria de Massas
12.
J Chromatogr A ; 1527: 33-42, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29089106

RESUMO

Carbotrap B as a highly pure surface sorbent with excellent adsorption/desorption properties was packed into a stainless steel needle to develop a new needle trap device (NTD). The performance of the prepared NTD was investigated for sampling, pre-concentration and injection of benzene, toluene, ethyl benzene, o-xylene, and p-xylene (BTEX) into the column of gas chromatography-mass spectrometry (GC-MS) device. Response surface methodology (RSM) with central composite design (CCD) was also employed in two separate consecutive steps to optimize the sampling and device parameters. First, the sampling parameters such as sampling temperature and relative humidity were optimized. Afterwards, the RSM was used for optimizing the desorption parameters including desorption temperature and time. The results indicated that the peak area responses of the analytes of interest decreased with increasing sampling temperature and relative humidity. The optimum values of desorption temperature were in the range 265-273°C, and desorption time were in the range 3.4-3.8min. The limits of detection (LODs) and limits of quantitation (LOQs) of the studied analytes were found over the range of 0.03-0.04ng/mL, and 0.1-0.13ng/mL, respectively. These results demonstrated that the NTD packed with Carbotrap B offers a high sensitive procedure for sampling and analysis of BTEX in concentration range of 0.03-25ng/mL in air.


Assuntos
Poluentes Atmosféricos/análise , Ar/análise , Monitoramento Ambiental/instrumentação , Monitoramento Ambiental/métodos , Compostos Orgânicos Voláteis/análise , Adsorção , Cromatografia Gasosa-Espectrometria de Massas , Limite de Detecção , Agulhas , Temperatura
13.
J Chromatogr A ; 1513: 27-34, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28734603

RESUMO

Some harmful volatile organic compounds (VOCs), such as methylbenzene, ethylbenzene, xylene, chlorobenzene and bromobenzene, are the commonly found chemicals in pen inks. In this work, a dynamic headspace needle-trap device (D-HS-NTD) with a ZIF-8-derived nanoporous carbon (ZIF-8-NPC) as the adsorbent was developed for the extraction of some VOCs in different pen inks prior to GC-MS detection. The main important influencing experimental parameters including the flow rate of the purge gas N2, extraction temperature, extraction time, desorption temperature and desorption time for the extraction were optimized to obtain a high extraction efficiency. Under the optimized conditions, a good linearity was obtained in the concentration range of 0.1-400µgkg-1 with the correlation coefficients (r) ranging from 0.9911 to 0.9990 for the eleven VOCs. The LODs at a signal-to-noise ratio of 3 (S/N=3) were measured to be 10-20ngkg-1 for the VOCs. The developed method was applied to determine the VOCs from 20 pen inks. The recoveries of the VOCs for the method at the spiking levels of 0.5 and 20.0µgkg-1 fell in the range from 80.0% to 108%.


Assuntos
Carbono/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Tinta , Compostos Orgânicos Voláteis/análise , Adsorção , Agulhas , Porosidade , Sensibilidade e Especificidade , Razão Sinal-Ruído , Propriedades de Superfície , Temperatura
14.
J Chromatogr A ; 1505: 1-17, 2017 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-28533027

RESUMO

Analysis of trace compounds in complex matrices requires a preliminary step of sample preparation. From among widely used methodologies, microextraction techniques have become increasingly important as they tend towards being environmentally friendly. The needle trap (NT) extraction is a relatively new and promising technique which combines sampling, sample preparation and sample introduction. The core of the needle trap device is a suitable sorbent material packed inside the needle, that determines selectivity and efficiency of the method. In recent years, the effort towards improvement of needle trap extraction performance has led to development of new extraction media with higher selectivity and better adsorption properties, which may facilitate preconcentration of the target analytes. In this work, we present a review on the trends in development of sorbent materials used in the needle trap device including fibrous media, commercially available materials as well as sorbents prepared for special applications. This review also describes recent developments in the needle trap devices such as needle geometries, sorbent packing procedure and sampling methodologies. Comparison of needle trap extraction and solid phase microextraction (SPME) is presented to demonstrate the robustness of the former.


Assuntos
Microextração em Fase Sólida/instrumentação , Adsorção , Agulhas , Microextração em Fase Sólida/métodos , Microextração em Fase Sólida/tendências
15.
Anal Chim Acta ; 975: 11-19, 2017 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-28552302

RESUMO

Cotton and silica are easily available and plentiful natural materials, with significant sorptive properties, which can be provided easily at low prices. In this research, a novel and effective sorbent was synthesized by covalent attachment of amino-silica/graphene oxide nanocomposite to the cotton (Cot/GO/Si) and packed into a stainless steel needle for preparation a needle trap device (NTD). The nanocomposite sorbent was characterized by SEM and FT-IR. The Cot/GO/Si packed NTD was used for direct extraction of PAHs from polluted soil samples, followed by GC-FID measurement. Different affecting experimental variables, including extraction temperature, flow rate, desorption time and temperature were studied and optimized. Under the optimal conditions, good linearity of the calibration curves (R2 > 0.99) was obtained over the concentration range of 0.01-1.0 µg g-1. The limits of detection, limits of quantification and relative standard deviations were found to be in the ranges of 0.05-0.17 ng g-1, 0.2-0.6 ng g-1 and 9.7-15.4% (n = 6), respectively. Finally, the proposed NTD-GC-FID method was successfully applied for the extraction and determination of PAHs in contaminated soil samples.

16.
Environ Monit Assess ; 189(4): 171, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28321678

RESUMO

In this research, a needle trap device (NTD) packed with nanoporous silica aerogel as a sorbent was used as a new technique for sampling and analysis of formaldehyde and acrolein compounds in aqueous and urine samples. The obtained results were compared with those of the commercial sorbent Carboxen1000. Active sampling was used and a 21-G needle was applied for extraction of gas in the sample headspace. The optimization of experimental parameters like salt addition, temperature and desorption time was done and the performance of the NTD for the extraction of the compounds was evaluated. The optimum temperature and time of desorption were 280 °C and 2 min, respectively. The ranges of limit of detection, limit of quantification and relative standard deviation (RSD) were 0.01-0.03 µg L-1, 0.03-0.1 µg L-1 and 2.8-7.3%, respectively. It was found that the NTD containing nanoporous silica aerogel had a better performance. Thus, this technique can be applied as an effective and reliable method for sampling and analysis of aldehyde compounds from different biological matrices like urine, exhalation and so on.


Assuntos
Acroleína/análise , Monitoramento Ambiental/instrumentação , Formaldeído/análise , Monitoramento Ambiental/métodos , Nanoporos , Agulhas , Dióxido de Silício/química , Temperatura
17.
J Chromatogr A ; 1464: 141-6, 2016 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-27545394

RESUMO

Vacuum ultraviolet (VUV) absorption spectroscopy was recently introduced as a new detection system for one, as well as comprehensive two-dimensional gas chromatography (GC×GC) and successfully applied to the analysis of various analytes in several matrices. In this study, its suitability for the analysis of breath metabolites was investigated and the impact of a finite volume of the absorption cell and makeup gas pressure was evaluated for volatile analytes in terms of sensitivity and chromatographic resolution. A commercial available VUV absorption spectrometer was coupled to GC×GC and applied to the analysis of highly polar volatile organic compounds (VOCs). Breath gas samples were acquired by needle trap micro extraction (NTME) during a glucose challenge and analysed by the applied technique. Regarding qualitative and quantitative information, the VGA-100 is compatible with common GC×GC detection systems like FID and even TOFMS. Average peak widths of 300ms and LODs in the lower ng range were achieved using GC×GC-VUV. Especially small oxygenated breath metabolites show intense and characteristic absorption patterns in the VUV region. Challenge responsive VOCs could be identified and monitored during a glucose challenge. The new VUV detection technology might especially be of benefit for applications in clinical research.


Assuntos
Testes Respiratórios/métodos , Cromatografia Gasosa/métodos , Compostos Orgânicos Voláteis/análise , Testes Respiratórios/instrumentação , Cromatografia Gasosa/instrumentação , Estudos de Viabilidade , Humanos , Limite de Detecção , Vácuo
18.
Anal Chim Acta ; 918: 43-9, 2016 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-27046209

RESUMO

In this paper solid phase microextraction (SPME) and needle trap device (NTD) as two in-progress air monitoring techniques was applied with silylated composite of carbon nanotubes for sampling and analysis of perchloroethylene in air. Application of SPME and NTD with proposed nano-structured sorbent was investigated under different laboratory and experimental parameters and compared to the SPME and NTD with CAR/PDMS. Finally the two samplers contained nano-sorbent used as a field sampler for sampling and analysis of perchloroethylene in dry cleaning. Results revealed that silica composite form of CNTs showed better performance for adsorbent of perchloroethylene. SPME and NTD with proposed sorbent was demonstrated better responses in lower levels of temperature and relative humidity. For 5 days from sampling the relative responses were more than 97% and 94% for NTD and SPME, respectively. LOD were 0.023 and 0.014 ng mL(-1) for SPME coated CNTs/SC and CAR/PDMS, and 0.014 and 0.011 ng mL(-1) for NTD packed with CNTs/SC and CAR/PDMS, respectively. And for consecutive analysis RSD were 3.9-6.7% in laboratory and 4.43-6.4% in the field. In the field study, NTD was successfully applied for determining of the PCE in dry cleaning. The results show that the NTD packed with nanomaterial is a reliable and effective approach for the sampling and analysis of volatile compounds in air.

19.
Environ Monit Assess ; 188(4): 238, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27003403

RESUMO

Treatment using cytotoxic drugs is considered to be the most common treatment for cancers. However, the widespread use of these drugs on the health status of the staff at the oncology department has become a great concern. Due to challenges of sampling and analysis of cytotoxic drugs, the aim of this study was to development a novel practical method called Needle trap devices (NTD) for sampling and analysis of personal exposure to cyclophosphamide drug. The sampler consisted of a stainless steel hyper needle gauge 21 of length 9 cm packed with Carboxen 1000 for adsorbing cyclophosphamide. A total of 41 samples of staff's air breathing zone in different wards of the oncology department were taken with the sampler. Samples were analyzed by gas chromatography coupled with electron capture detector (ECD). Linear range concentration was 212-1062 µg/m(3), and LOD and LOQ were 100 and 191 µg/m(3), respectively. The mean inter-day and intra-day coefficient variations for standards within linear range concentration were 8.9 and 4.8 %, respectively. Detectable levels of cyclophosphamide were measured in 31.7 % of air samples. The developed method is user-friendly, quick, and precise for sampling of airborne cyclophosphamide. The results showed that some staff of the oncology department were exposed to the carcinogenic drug and their health were at risk. Since carcinogens do not have a threshold and oncology staffs with their continuous exposure might be at risk, therefore, proper work practice and adequate control measures are essential to ensure their wellbeing.


Assuntos
Antineoplásicos/toxicidade , Ciclofosfamida/toxicidade , Monitoramento Ambiental/métodos , Exposição Ocupacional/análise , Antineoplásicos/análise , Antineoplásicos/metabolismo , Cromatografia Gasosa , Ciclofosfamida/análise , Ciclofosfamida/metabolismo , Humanos , Exposição Ocupacional/estatística & dados numéricos , Enfermagem Oncológica
20.
J Sep Sci ; 38(24): 4225-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26459611

RESUMO

In this study, the application of a novel nanomaterial composite was investigated in two microextraction techniques of solid-phase microextraction and a needle trap device in a variety of sampling conditions. The optimum sampling temperature and relative humidity were 10°C and 20%, respectively, for both techniques with two sorbents of graphene/silica composite and polydimethyl siloxane. The two microextraction techniques with the proposed sorbent showed recoveries of 95.2 and 94.6% after 7 days. For the needle trap device the optimums desorption time and temperature were 3 min at 290°C and for SPME these measures were 1 and 1.5 min at 240-250°C for the graphene/silica composite and polydimethyl siloxane, respectively. The relative standard division obtained in inter- and intra-day comparative studies were 3.3-14.3 and 5.1-25.4, respectively. For four sample the limit of detection was 0.021-0.25 ng/mL, and the limit of quantitation was 0.08-0.75 ng/mL. The results show that the graphene/silica composite is an appropriate extraction media for both techniques. Combining an appropriate sorbent with microextraction techniques, and using these in conjunction with a sensitive analytical instrument can introduce a strong method for sampling and analysis of occupational and environmental pollutants in air.

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