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Volatile organic compound analysis

Lanling Chu, Siwei Deng, Renshan Zhao, Jianjun Deng, Xuejun Kang
The objective of this study was to compare the adsorption/desorption of target compounds on homemade electrospun nanofibers, polystyrene (PS) nanofibers, acrylic resin (AR) nanofibers and PS-AR composite nanofibers with Tenax TA. Ten volatile organic compounds (VOCs) were analyzed by preconcentration onto different sorbents followed by desorption (thermal and solvent orderly) and analysis by capillary gas chromatography. In comparison to Tenax TA, the electrospun nanofibers displayed a significant advantage in desorption efficiency and adsorption selectivity...
2016: PloS One
Wen-Long Li, Wan-Li Ma, Hongliang Jia, Wenjun Hong, Hyo-Bang Moon, Haruhiko Nakata, Nguyen Hung Minh, Ravindra Kumar Sinha, Kai Hsien Chi, Kurunthachalam Kannan, Ed Sverko, Yi-Fan Li
A total of 23 PBDE congeners were measured in soil samples collected in areas with no known point source (urban/rural/background sites, U/R/B sites) and in contaminated areas (brominated flame retardants (BFRs) related industrial and e-waste recycling sites) across five Asian countries. The highest PBDE concentrations were found in BFRs related industrial and e-waste recycling sites. The concentrations of PBDEs in U/R/B sites followed the order of: urban > rural > background sites. Total PBDE concentrations were dominated by BDE-209, while BDE-17, -85, -138, -191, -204 and -205 were the least abundant compounds...
October 24, 2016: Environmental Science & Technology
Laura Capelli, Gianluigi Taverna, Alessia Bellini, Lidia Eusebio, Niccolò Buffi, Massimo Lazzeri, Giorgio Guazzoni, Giorgio Bozzini, Mauro Seveso, Alberto Mandressi, Lorenzo Tidu, Fabio Grizzi, Paolo Sardella, Giuseppe Latorre, Rodolfo Hurle, Giovanni Lughezzani, Paolo Casale, Sara Meregali, Selena Sironi
The electronic nose is able to provide useful information through the analysis of the volatile organic compounds in body fluids, such as exhaled breath, urine and blood. This paper focuses on the review of electronic nose studies and applications in the specific field of medical diagnostics based on the analysis of the gaseous headspace of human urine, in order to provide a broad overview of the state of the art and thus enhance future developments in this field. The research in this field is rather recent and still in progress, and there are several aspects that need to be investigated more into depth, not only to develop and improve specific electronic noses for different diseases, but also with the aim to discover and analyse the connections between specific diseases and the body fluids odour...
October 14, 2016: Sensors
Anandram Venkatasubramanian, Vincent T K Sauer, Swapan K Roy, Mike Xia, David S Wishart, Wayne K Hiebert
Micro-Gas Chromatography (GC) is promising for portable chemical analysis. We demonstrate a nano-optomechanical system (NOMS) as an ultrasensitive mass detector in gas chromatography. Bare, native oxide, silicon surfaces are sensitive enough to monitor volatile organic compounds at ppm levels, while simultaneously demonstrating chemical selectivity. The NOMS is able to sense GC peaks from derivatized metabolites at physiological concentrations. This is an important milestone for small-molecule quantitation assays in next generation metabolite analyses for applications such as disease diagnosis and personalized medicine...
October 17, 2016: Nano Letters
Guozhu Zhao, Guohua Yin, Arati A Inamdar, Jing Luo, Ning Zhang, Ill Yang, Brian Buckley, Joan W Bennett
Super Storm Sandy provided an opportunity to study filamentous fungi (molds) associated with winter storm damage. We collected 36 morphologically distinct fungal isolates from flooded buildings. By combining traditional morphological and cultural characters with an analysis of ITS sequences (the fungal DNA barcode), we identified 24 fungal species that belong to 8 genera: Penicillium (12 species), Fusarium (4 species), Aspergillus (3 species), Trichoderma (2 species), and one species each of Metarhizium, Mucor, Pestalotiopsis, and Umbelopsis...
October 17, 2016: Indoor Air
Kenion H Blakeman, Craig A Cavanaugh, William M Gilliland, J Michael Ramsey
RATIONALE: There are many chemical measurement scenarios that would benefit from hand portable mass spectrometry tools including forensics, environmental monitoring, and safety and security. High pressure mass spectrometry (HPMS) facilitates miniaturization by significantly reducing vacuum system requirements. Previous work demonstrated HPMS using helium buffer gas, but HPMS conducted using ambient air would further reduce the size and weight of a portable instrument while also reducing logistical demands by eliminating the need for a helium supply...
October 17, 2016: Rapid Communications in Mass Spectrometry: RCM
Sean W Harshman, Nilan Mani, Brian A Geier, Jae Kwak, Phillip Shepard, Maomian Fan, Gregory L Sudberry, Ryan S Mayes, Darrin K Ott, Jennifer A Martin, Claude C Grigsby
Exhaled breath is coming to the forefront of non-invasive biomarker discovery efforts. Concentration of exhaled breath volatile organic compounds (VOCs) on thermal desorption (TD) tubes with subsequent analysis by gas chromatography-mass spectrometry (GC-MS) has dominated this field. As discovery experimentation increases in frequency, the need to evaluate the long-term storage stability of exhaled breath VOCs on thermal desorption adsorbent material is critical. To address this gap, exhaled breath was loaded on Tenax TA thermal desorption tubes and stored at various temperature conditions...
October 12, 2016: Journal of Breath Research
Kristin Schallschmidt, Roland Becker, Christian Jung, Wolfram Bremser, Thorsten Walles, Jens Neudecker, Gunda Leschber, Steffen Frese, Irene Nehls
This paper outlines the design and performance of an observational study on the profiles of volatile organic compounds (VOCs) in the breath of 37 lung cancer patients and 23 healthy controls of similar age. The need to quantify each VOC considered as a potential disease marker on the basis of individual calibration is elaborated, and the quality control measures required to maintain reproducibility in breath sampling and subsequent instrumental trace VOC analysis using solid phase microextraction-gas chromatography-mass spectrometry over a study period of 14 months are described...
October 12, 2016: Journal of Breath Research
Philip B Pedros, Omid Askari, Hameed Metghalchi
During the last decade municipal wastewater treatment plants have been regulated with increasingly stringent nutrient removal requirements including nitrogen. Typically biological treatment processes are employed to meet these limits. Although the nitrogen in the wastewater stream is reduced, certain steps in the biological processes allow for the release of gaseous nitrous oxide (N2O), a greenhouse gas (GHG). A comprehensive study was conducted to investigate the potential to mitigate N2O emissions from biological nutrient removal (BNR) processes by means of thermal decomposition...
October 4, 2016: Water Research
Rongyu Zhuang, Yongjiang Lou, Xiaoting Qiu, Yangyong Zhao, Dong Qian, Xiaojun Yan, Xiaodie He, Qingqing Shen, Lizhen Qian
Hydrogen sulfide is a common odor gas of volatile sulfur-containing compound. The emission of hydrogen sulfide in the waste gas from industrial processing and agricultural operations could cause air pollution to the surrounding environment. The aim of this study was screening and isolation of wild yeast strains from the sludge of sewage pool in the fishmeal processing plant to remove hydrogen sulfide odor. A yeast strain ZJY-7 was obtained. Its hydrogen sulfide removal efficiency was 97.1 %. The morphology studies were investigated using microscope and scanning electron microscope...
October 10, 2016: Applied Microbiology and Biotechnology
Marie Chantal Lemfack, Srinivasa Rao Ravella, Nicola Lorenz, Marco Kai, Kirsten Jung, Stefan Schulz, Birgit Piechulla
The skin microbiota is import for body protection. Here we present the first comprehensive analysis of the volatile organic compound (VOC) profiles of typical skin-resident corynebacterial and staphylococcal species. The VOC profile of Staphylococcus schleiferi DSMZ 4807 was of particular interest as it is dominated by two compounds, 3-(phenylamino)butan-2-one and 3-(phenylimino)butan-2-one (schleiferon A and B, respectively). Neither of these has previously been reported from natural sources. Schleiferon A and B inhibited the growth of various Gram-positive species and affected two quorum-sensing-dependent phenotypes - prodigiosin accumulation and bioluminescence - of Gram-negative bacteria...
September 27, 2016: Systematic and Applied Microbiology
Luke Bell, Lisa Methven, Angelo Signore, Maria Jose Oruna-Concha, Carol Wagstaff
Sensory and chemical analyses were performed on accessions of rocket (Eruca sativa) to determine phytochemical influences on sensory attributes. A trained panel was used to evaluate leaves, and chemical data were obtained for polyatomic ions, amino acids, sugars and organic acids. These chemical data (and data of glucosinolates, flavonols and headspace volatiles previously reported) were used in Principal Component Analysis (PCA) to determine variables statistically important to sensory traits. Significant differences were observed between samples for polyatomic ion and amino acid concentrations...
March 1, 2017: Food Chemistry
Alexander L Vogel, Johannes Schneider, Christina Müller-Tautges, Thomas Klimach, Thorsten Hoffmann
Atmospheric oxidation of volatile organic compounds (VOCs) yields a large number of different organic molecules which comprise a wide range of volatility. Depending on their volatility, they can be involved in new particle formation and particle growth, thus affecting the number concentration of cloud condensation nuclei in the atmosphere. Here, we identified oxidation products of VOCs in the particle phase during a field study at a rural mountaintop station in central Germany. We used atmospheric pressure chemical ionization mass spectrometry ((-)APCI-MS) and aerosol mass spectrometry for time-resolved measurements of organic species and of the total organic aerosol (OA) mass in the size range of 0...
October 6, 2016: Environmental Science & Technology
Stefania Carpino, Cinzia L Randazzo, Alessandra Pino, Nunziatina Russo, Teresa Rapisarda, Gianni Belvedere, Cinzia Caggia
The objectives of the present study were to characterize the biofilm microbiota of 11 different farms (from A to K), producing PDO Ragusano cheese, and to investigate on its ability to generate volatile organic compounds (VOCs) in milk samples inoculated with biofilm and incubated under Ragusano cheese making conditions. The biofilms were subjected to plate counting and PCR/T/DGGE analysis and the VOCs generated in incubated milk samples were evaluated through SmartNose, GC/O, and GC/MS. Streptococcus thermophilus was the dominant species both in biofilms and in incubated milks...
February 2017: Food Microbiology
Yan Qin, Yingming Pang, Zhihong Cheng
INTRODUCTION: The needle trap device (NTD) technique is a new microextraction method for sampling and preconcentration of volatile organic compounds (VOCs). Previous NTD studies predominantly focused on analysis of environmental volatile compounds in the gaseous and liquid phases. Little work has been done on its potential application in biological samples and no work has been reported on analysis of bioactive compounds in essential oils from herbal medicines. OBJECTIVE: The main purpose of the present study is to develop a NTD sampling method for profiling VOCs in biological samples using herbal medicines as a case study...
November 2016: Phytochemical Analysis: PCA
Kristina L Hitzfeld, Matthias Gehre, Hans-Hermann Richnow
In this study conversion conditions for oxygen gas chromatography high temperature conversion (HTC) isotope ratio mass spectrometry (IRMS) are characterised using qualitative mass spectrometry (IonTrap). It is shown that physical and chemical properties of a given reactor design impact HTC and thus the ability to accurately measure oxygen isotope ratios. Commercially available and custom-built tube-in-tube reactors were used to elucidate (i) by-product formation (carbon dioxide, water, small organic molecules), (ii) 2nd sources of oxygen (leakage, metal oxides, ceramic material), and (iii) required reactor conditions (conditioning, reduction, stability)...
August 16, 2016: Isotopes in Environmental and Health Studies
Shanshan Xie, Haoyu Zang, Huijun Wu, Uddin Rajer Faheem, Xuewen Gao
Recent investigations have demonstrated that bacteria employ the volatile compounds they produce during interactions with other organisms such as plants, fungi, nematodes and bacteria. However, studies focused on the antibacterial activity of plant growth promoting rhizobacteria (PGPR) volatiles against bacterial phytopathogens are still rare. In this study, Bacillus strain D13, which is antagonistic to Xanthomonas oryzae pv. oryzae (Xoo), was isolated and screened. Volatile compounds emitted from strain D13 reduced the colony diameter and cell motility of Xoo cultured in divided Petri plates...
September 29, 2016: Molecular Plant Pathology
Yoro Tine, Abdoulaye Diop, William Diatta, Jean-Marie Desjobert, Cheikh Saad Bouh Boye, Jean Costa, Alassane Wélé, Julien Paolini
The chemical diversity of Z. zanthoxyloides growing wild in Senegal was studied according to volatile compound classes, plant organs and sample locations. The composition of fruit essential oil was investigated using an original targeted approach based on the combination of gas chromatography (GC) and liquid chromatography (LC) both coupled with mass spectrometry (MS). The volatile composition of Z. zanthoxyloides fruits exhibited relative high amounts of hydrocarbon monoterpenes (24.3-55.8%) and non-terpenic oxygenated compounds (34...
September 28, 2016: Chemistry & Biodiversity
Kevin Lamote, Matthijs Vynck, Joris Van Cleemput, Olivier Thas, Kristiaan Nackaerts, Jan P van Meerbeeck
Malignant pleural mesothelioma (MPM) is predominantly caused by previous asbestos exposure. Diagnosis often happens in advanced stages restricting any therapeutic perspectives. Early stage detection via breath analysis was explored using multicapillary column/ion mobility spectrometry (MCC/IMS) to detect volatile organic compounds (VOCs) in the exhaled breath of MPM patients in comparison to former occupational asbestos-exposed and non-exposed controls. Breath and background samples of 23 MPM patients, 22 asymptomatic former asbestos (AEx) workers and 21 healthy non-asbestos exposed persons were taken for analysis...
2016: Journal of Breath Research
Waseem Raza, Ning Ling, Dongyang Liu, Zhong Wei, Qiwei Huang, Qirong Shen
The volatile organic compounds (VOCs) produced by soil microbes have a significant role in the control of plant diseases and plant growth promotion. In this study, we examined the effect of VOCs produced by Pseudomonas fluorescens strain WR-1 on the growth and virulence traits of tomato wilt pathogen Ralstonia solanacearum. The VOCs produced by P. fluorescens WR-1 exhibited concentration dependent bacteriostatic effect on the growth of R. solanacearum on agar medium and in infested soil. The VOCs of P. fluorescens WR-1 also significantly inhibited the virulence traits of R...
November 2016: Microbiological Research
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