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Jakub W Trzciński, Roberta Pinalli, Nicolò Riboni, Alessandro Pedrini, Federica Bianchi, Stefano Zampolli, Ivan Elmi, Chiara Massera, Franco Ugozzoli, Enrico Dalcanale
In this work we report a comprehensive study leading to the fabrication of a prototype sensor for environmental benzene monitoring. The required high selectivity and ppb-level sensitivity are obtained by coupling a silicon-integrated concentration unit containing the specifically designed EtQxBox cavitand to a miniaturized PID detector. In the resulting stand-alone sensor, the EtQxBox receptor acts at the same time as highly sensitive preconcentrator for BTEX and GC-like separation phase, allowing for the selective desorption of benzene over TEX...
April 28, 2017: ACS Sensors
Magdalena Cerkowniak, Mieczysława I Boguś, Emilia Włóka, Piotr Stepnowski, Marek Gołębiowski
A constant problem in veterinary medicine, human healthcare, agriculture, forestry or horticulture is the large number of pests, and the lack of effective methods to combat them which cause no harm to the rest of the environment. It is recommended and desired to reduce the use of chemicals and increase the use of agents based on the knowledge acquired in the field of biology, chemistry, and agrochemicals. To learn the defense mechanisms of insects we should consider not only the site of their physiological ability to protect against external factors (cuticle), but also check the possibility of chemical protection, formed by all compounds on the surface and in the body of insects...
July 19, 2017: Biomedical Chromatography: BMC
Germán Augusto Gómez-Ríos, Tijana Vasiljevic, Emanuela Gionfriddo, Miao Yu, Janusz Pawliszyn
On-site screening for target analytes in complex matrices, such as biofluids and food specimens, not only requires reliable and portable analytical instrumentation, but also solvent-free and easy-to-use sampling/sample preparation approaches that allow analytes of interest to be isolated from such matrices. The integration of sampling devices with field deployable instruments should be as efficient as possible, and should aim to provide rapid, precise, and accurate results that enable quick on-site decision...
July 19, 2017: Analyst
Jianping Cao, Ningrui Liu, Yinping Zhang
Clothes play an important role in dermal exposure to indoor semi-volatile organic compounds (SVOCs). The diffusion coefficient of SVOCs in clothing material (Dm) is essential for estimating SVOC sorption by clothing material and subsequent dermal exposure to SVOCs. However, few studies have reported the measured Dm for clothing materials. In this paper, we present the solid-phase micro-extraction (SPME) based Ca-history method. To the best of our knowledge, this is the first try to measure Dm with known relative standard deviation (RSD)...
July 17, 2017: Environmental Science & Technology
Benhamimed El-Attafia, Moulessehoul Soraya
BACKGROUND: The use of chlorine to disinfect water, produces various disinfection byproducts such as trihalomethanes (THMs). These compounds are formed when free available chlorine reacts with natural organic matter in raw water during water disinfection. Epidemiologic studies have shown an association between long-term exposure to THMs and an increased risk of cancer, all of them are suspected of having carcinogenic effects. AIM: The aim of this study was to determine the presence of THMs in the drinking tap water of Mostaganem Province (Algeria) in order to assess the seasonal variation in trihalomethane levels in tap water and to identify the season of high risk to the consumer...
May 2017: Electronic Physician
Jian Chen
Headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) is commonly used in analyzing insect volatiles. In order to improve the detection of volatiles in insects, a freeze-thaw method was applied to insect samples before the HS-SPME-GC-MS analysis. Insect samples were first frozen at -80 ⁰C for 10 min and then thawed at 25 ⁰C for 5 min before SPME extraction was performed. The freeze-thaw method clearly improved the detection of volatile compounds for all six tested insect species, including red imported fire ants, Solenopsis invicta Buren, black imported fire ants, Solenopsis richteri Forel, little black ants, Monomorium minimum (Buckley), pharaoh ants, Monomorium pharaonis (Linnaeus); eastern subterranean termites, Reticulitermes flavipes (Kollar); and spotted lady beetles, Coleomegilla maculate De Geer...
July 17, 2017: Analytical Chemistry
Cuicui Wang, Linyan Yang, Na Li, Xinda Zhang, Yongze Guo, Cun Li
In this study, immunoaffinity solid phase microextraction (SPME) rods were developed for the analysis of diethylstilbestrol (DES), hexestrol (HES) and dienestrol (DIS) followed by ultra high-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). This immunoaffinity SPME device was built with three stainless steel rods bundled together as one and modified with porous silicate particles. As an extraction sorbent, antibody immobilization approach was employed based on the covalent attachment of the anti-diethylstilbestrol monoclonal antibody (mAb) onto the rods...
July 6, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Mouna Ben Rached, Gianni Galaverna, Martina Cirlini, Dalenda Boujneh, Mokhtar Zarrouk, Mokhtar Guerfel
The aim of this study examined the characterization of extra virgin olive oil samples from the main cultivar Chemlali, grown in five olive orchards with different soil type (Sandy, Clay, Stony, Brown, Limestone and Gypsum). Volatile compounds were studied using headspace-solid phase micro-extraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS) technics. Moreover, the sterol profile was established using gas chromatography-mass spectrometry. 35 different volatile compounds were identified: alcohols, esters, aldehydes, ketones and hydrocarbons...
July 12, 2017: Journal of Oleo Science
Yoshinori Asakawa, Kenichi Tomiyama, Kazutoshi Sakurai, Yukihiro Kawakami, Yoshihiro Yaguchi
The volatile compounds obtained from the different organs of Houttuynia cordata (Saururaceae) and Litsea cubeba (Lauraceae) were analyzed by Gas Chromatography/Mass Spectrometry (GC/MS), Headspace Solid Phase Micro Extraction-Gas Chromatography/Mass Spectrometry (HS-SPME-GC/MS), and GC/olfactometry (GC/O). The major component of all parts of H. cordata is assigned as 4-tridecanone. Each organ produces myrcene as the major monoterpenoid. The major monoterpene in the rhizomes and roots was β-pinene instead of myrcene...
July 12, 2017: Journal of Oleo Science
Sana Abdolhosseini, Alireza Ghiasvand, Nahid Heidari
The surface of a stainless steel fiber was made porous, resistant and cohesive using electrophoretic deposition and coated by the nanostructured polypyrrole using an amended in-situ electropolymerization method. The coated fiber was applied for direct extraction of nicotine in biological samples through a headspace solid-phase microextraction (HS-SPME) method followed by GC-FID determination. The effects of the important experimental variables on the efficiency of the developed HS-SPME-GC-FID method, including pH of sample solution, extraction temperature and time, stirring rate, and ionic strength were evaluated and optimized...
June 27, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Alexander A Aksenov, Konstantin O Zamuruyev, Alberto Pasamontes, Joshua F Brown, Michael Schivo, Soraya Foutouhi, Bart C Weimer, Nicholas J Kenyon, Cristina E Davis
Breath analysis has been gaining popularity as a non-invasive technique that is amenable to a broad range of medical uses. One of the persistent problems hampering the wide application of the breath analysis method is measurement variability of metabolite abundances stemming from differences in both sampling and analysis methodologies used in various studies. Mass spectrometry has been a method of choice for comprehensive metabolomic analysis. For the first time in the present study, we juxtapose the most commonly employed mass spectrometry-based analysis methodologies and directly compare the resultant coverages of detected compounds in exhaled breath condensate in order to guide methodology choices for exhaled breath condensate analysis studies...
June 27, 2017: Journal of Chromatography. B, Analytical Technologies in the Biomedical and Life Sciences
Han-Peng Jiang, Ting Liu, Ning Guo, Lei Yu, Bi-Feng Yuan, Yu-Qi Feng
Nucleic acids carry diverse chemical modifications that exert critical influences in a variety of cellular processes in living organisms. In addition to methylation, the emerging DNA and RNA formylation has been reported to play functional roles in various physiological processes. However, the amounts of formylated DNA and RNA are extremely low and detection of DNA and RNA formylation is therefore a challenging task. To address this issue, we developed a strategy by chemical labeling combined with in-tube solid-phase microextraction - ultra high performance liquid chromatography - electrospray ionization - tandem mass spectrometry (in-tube SPME-UPLC-ESI-MS/MS) analysis for the sensitive determination of DNA and RNA formylation...
August 15, 2017: Analytica Chimica Acta
Waseem Raza, Xinlan Mei, Zhong Wei, Ning Ling, Jun Yuan, Jichen Wang, Qiwei Huang, Qirong Shen
The complexity of soil processes involved in the production, consumption and accumulation of volatile organic compounds (VOCs) makes hard to access the overall dynamics of VOCs in the soil. In this study, the field soil, applied with inorganic (CF), organic (OF) and inorganic-organic mixed (CFOF) fertilizers for ten years was evaluated for the emission of VOCs at different temperature and moisture levels. We identified 30-50 soil emitted VOCs representing the most common soil VOCs groups by using the solid-phase microextraction (SPME) fiber and gas chromatography-mass spectroscopy...
July 7, 2017: Science of the Total Environment
Sirwan Mohammadiazar, Nastaran Fallahpour, Ali Roostaie, Bahram Ebrahimi
In this study a novel technique is proposed for preparation of an efficient and unbreakable metal-wire-supported solid-phase microextraction fiber. A sol-gel film was deposited on electrophoretically deposited carbon nanotubes on a stainless-steel wire. The applicability of the fiber was evaluated through the extraction of some aromatic pollutants as model compounds from the headspace of aqueous samples in combination with gas chromatography and mass spectrometry. The parameters affecting the structure and extraction efficiency of the fiber (including the type of solvent, time and potential for electrophoretic deposition) and the parameters affecting the extraction efficiency (such as coating type, salt content, extraction temperature and time) were investigated...
July 10, 2017: Journal of Separation Science
Lijun Xie, Shuqin Liu, Zhubing Han, Ruifen Jiang, Fang Zhu, Weiqin Xu, Chengyong Su, Gangfeng Ouyang
The fiber coating is the key part of the solid-phase microextraction (SPME) technique, and it determines the sensitivity, selectivity, and repeatability of the analytical method. In this work, amine (NH2)-functionalized material of Institute Lavoisier (MIL)-53(Al) nanoparticles were successfully synthesized, characterized, and applied as the SPME fiber coating for efficient sample pretreatment owing to their unique structures and excellent adsorption properties. Under optimized conditions, the NH2-MIL-53(Al)-coated fiber showed good precision, low limits of detection (LODs) [0...
July 6, 2017: Analytical and Bioanalytical Chemistry
Kanjana Mahattanatawee, Torsak Luanphaisarnnont, Russell Rouseff
Thummong (Litsea petiolata Hook. f.) is a tree native to southern Thailand. The leaves of this tree are highly aromatic and used to flavor Thai dishes in place of the traditional water beetle Mangdana (Lethocerus indicus) for religious and cultural reasons. Total and aroma-active volatiles from both flavoring materials were compared using gas chromatography-olfactory (GC-O) and gas chromatography-mass spectrometry (GC-MS). The volatiles from Thummong leaves and the Mangdana water beetle were collected and concentrated using headspace solid-phase microextraction...
July 11, 2017: Journal of Agricultural and Food Chemistry
Josephine Al-Alam, Ziad Fajloun, Asma Chbani, Maurice Millet
An optimized analytical method was developed for the simultaneous analysis of 90 pesticides, 16 polycyclic aromatic hydrocarbons, and 22 polychlorinated biphenyls. The method was based on quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction using acetonitrile followed by a dispersive solid-phase extraction cleanup using primary-secondary amine and octadecyl (C18). The extract obtained was concentrated by evaporation and then reconstituted with acetonitrile to prepare it for chromatographic analysis by liquid chromatography-triple-quadrupole tandem mass spectrometry and gas chromatography-ion-trap tandem mass spectrometry, which was preceded by a preconcentration step using solid-phase microextraction with appropriate fibers...
July 5, 2017: Analytical and Bioanalytical Chemistry
Amila M Devasurendra, Cheng Zhang, Joshua A Young, L M Viranga Tillekeratne, Jared L Anderson, Jon R Kirchhoff
Pyrrole was covalently bonded to 1-methyl and 1-benzylimidazolium ionic liquids (ILs) via an N-substituted alkyl linkage to prepare electropolymerizable IL monomers with excellent thermal stability. The methylimidazolium IL, [pyrrole-C6MIm](+), was then electropolymerized on macro- and microelectrode materials to form conductive polymeric IL (CPIL)-modified surfaces. Electrochemical characterization of a 1.6 mm diameter Pt disk electrode modified with poly[pyrrole-C6MIm](+) demonstrated a selective uptake for an anionic redox probe while rejecting a cationic redox probe...
July 17, 2017: ACS Applied Materials & Interfaces
Piotr M Kuś, Igor Jerković, Zvonimir Marijanović, Carlo I G Tuberoso
GC-MS of HS-SPME and solvent extractives along with targeted HPLC-DAD of Polish fir (Abies alba Mill.) honeydew honey (FHH), were used to determine the chemical profiles and potential markers of botanical origin. Additionally, typical physical-chemical parameters were also assigned. The values determined for FHH were: conductivity (1.2 mS/cm), water content (16.7 g/100 g), pH (4.5) and CIE chromaticity coordinates (L* = 48.4, a* = 20.6, b* = 69.7, C* = 72.9 and h° = 73.5). FHH contained moderate-high total phenolic content (533...
June 28, 2017: Chemistry & Biodiversity
Hamdi Bendif, Mohamed Djamel Miara, Gregorio Peron, Stefania Sut, Stefano Dall'Acqua, Guido Flamini, Filippo Maggi
In this work a comprehensive study on the chemical constituents of the aerial parts of Rosmarinus eriocalyx L. (Lamiaceae), an aromatic shrub traditionally consumed as a food and herbal remedy in Algeria, is presented. The aroma profile was analysed by headspace solid phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS), whereas the crude extract constituents were analyzed by (1) H-NMR and by high-performance liquid chromatography coupled with mass spectrometry (HPLC-MS(n) )...
June 28, 2017: Chemistry & Biodiversity
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