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Breathomics and its Application for Disease Diagnosis: A Review of Analytical Techniques and Approaches
Published in Raquel Cumeras, Xavier Correig, Volatile organic compound analysis in biomedical diagnosis applications, 2018
David J. Beale, Oliver A. H. Jones, Avinash V. Karpe, Ding Y. Oh, Iain R. White, Konstantinos A. Kouremenos, Enzo A. Palombo
Ion mobility spectrometry (IMS) is an analytical technique used to separate and identify ionized molecules in the gas phase based on their mobility in a carrier buffer gas and, when coupled with MS (e.g., IMS-MS), enables additional separation of ions by their mass-to-charge (m/z) ratio (Lanucara et al., 2014). Furthermore, there are few variants of IMS that enable the use of an external electric field at ambient pressure and temperatures in order to separate different ions formed from the target analytes; these include differential mobility spectrometers (DMS) and high-field asymmetric waveform ion mobility spectrometers (FAIMS) (Pereira et al., 2015). Generally, IMS is commonly used to detect explosives, chemical warfare agents or illegal drugs but more recently has been used to analyze VOCs in breath (Halbfeld et al., 2014). Typically, VOC detection limits using IMS are of the magnitude of pg/L to ng/L-range, and when IMS is coupled with a multi-capillary column as a breath-sampling device, the analysis can be performed in under 8 min and at the site of sampling (Handa et al., 2014).
Effects of drying temperature on the drying characteristics and volatile profiles of Citrus reticulata Blanco peels under two stages of maturity
Published in Drying Technology, 2022
Jun Wang, Hui Wang, Hong-Wei Xiao, Xiao-Ming Fang, Wei-Peng Zhang, Chang-Lu Ma
In recent years, the successful combination of ion mobility spectrometry (IMS) and chromatography (GC) has facilitated the identification of volatile compounds. Headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) has been widely applied in the food field due to its advantages of ultra-high analytical speed and sensitivity, low detection limits, and operating at atmospheric pressure without sample preparation.[15,16] The characteristics and changes of volatile compounds in Tricholoma matsutake Singer,[15,16], apple,[17] and citrus[18] have been studied through the establishment of fingerprints by HS-GC-IMS and principal component analysis (PCA) based on identified volatile compounds. It is a common phenomenon that citrus fruits are harvested about 10 days or more before normal ripening, which can prevent soft and rotten losses due to over-maturity during long-time transportation. In addition, these early-harvested citruses usually have a lower sugar-acid ratio, which caters to some consumers' preference for sour fruits. Fruit maturity has a significant influence on its volatile profiles.[19] For citrus, the peel of mature fruit is yellow and that of unripe fruit is green. However, the impact of citrus ripeness on volatile compounds in the peel during drying processing has not been reported to the authors’ knowledge.
Determination of chemical warfare agents by low cost differential mobility spectrometry
Published in Instrumentation Science & Technology, 2021
Dongjie Zhao, Xianqiang Li, Siqing You, Xi Yang, Jun Liu
In recent years, a series of rapid analytical methods have been available for gas sensors, as advanced micro- and nano-fabrication technology enables miniaturization of the core components into microsized volume.[5,6] High-field asymmetric waveform ion mobility spectrometry (FAIMS), also called differential mobility spectrometry (DMS),[7] is an atmospheric pressure gas-phase separation technique which separates gas phase ions based upon nonlinear compound-dependent differences of their mobilities in alternating high and low electric fields.[8] DMS has attracted attention due to its small volume, low cost,[9] and high sensitivity.[10,11] Compared other gas sensors, DMS uses spectral analysis to determine gas molecules with high resolution and sensitivity, which has been employed in environmental monitoring, food safety, explosives, and drug development.[12–14]
Facile solvothermal syntheses of isostructural lanthanide(III) formates: Photocatalytic, photoluminescent chemosensing properties, and proficient precursors for metal oxide nanoparticles
Published in Journal of Coordination Chemistry, 2021
Sidra Farid, Saima Ameen, Shahzad Sharif, Madiha Tariq, Israr Ahmad Kundi, Onur Sahin, Muhammd Hassan Sayyad, Islam Ullah Khan
Besides water security, homeland security is also important with sensitive and efficient methods for rapid detection of explosives needed. Sophisticated instrumental techniques like GCMS, Raman spectroscopy, ion mobility spectrometry (IMS), and some simple approaches, including metal detectors and canines, are commonly used for explosive detection [31, 32]. Instrumental methods are expensive and challenging to use at onsite field testing; metal detectors are only suitable for metal containing explosive gadgets while canines are expensive, quickly exhausted and require proper care. Nitro-aromatics are compounds frequently used in explosives. Picric acid and trinitrotoluene are the two most common compounds of this class used in fireworks, rocket fuels, landmines, matches, dyes, pesticides, and many other commodities [33]. Picric acid is a more powerful explosive than trinitrotoluene and has a low safety coefficient. It can cause severe liver malfunction, respiratory disorders, dermatological issues, and many other chronic diseases [34]. Fluorescence sensing is the most sensitive, portable, cost-efficient method for nitro-aromatic detection and also requires simple instrumentation, facile sample preparation, and quick response.