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Ambient ionization

Xiangyu Guo, Hua Bai, Yueguang Lv, Guangcheng Xi, Junfang Li, Xiaoxiao Ma, Yue Ren, Zheng Ouyang, Qiang Ma
Rapid, on-site analysis was achieved through significantly simplified operation procedures for a wide variety of toy samples (crayon, temporary tattoo sticker, finger paint, modeling clay, and bubble solution) using a miniature mass spectrometry system with ambient ionization capability. The labor-intensive analytical protocols involving sample workup and chemical separation, traditionally required for MS-based analysis, were replaced by direct sampling analysis using ambient ionization methods. A Mini β ion trap miniature mass spectrometer was coupled with versatile ambient ionization methods, e...
April 1, 2018: Talanta
Felipe J Lara-Ortega, Miriam Beneito-Cambra, José Robles-Molina, Juan F García-Reyes, Bienvenida Gilbert-López, Antonio Molina-Díaz
Analytical methods based on ambient ionization mass spectrometry (AIMS) combine the classic outstanding performance of mass spectrometry in terms of sensitivity and selectivity along with convenient features related to the lack of sample workup required. In this work, the performance of different mass spectrometry-based methods has been assessed for the direct analyses of virgin olive oil for quality purposes. Two sets of experiments have been setup: (1) direct analysis of untreated olive oil using AIMS methods such as Low-Temperature Plasma Mass Spectrometry (LTP-MS) or paper spray mass spectrometry (PS-MS); or alternatively (2) the use of atmospheric pressure ionization (API) mass spectrometry by direct infusion of a diluted sample through either atmospheric pressure chemical ionization (APCI) or electrospray (ESI) ionization sources...
April 1, 2018: Talanta
Bin Hu, Zhong-Ping Yao
Detection of native proteins, particularly directly from raw biological samples, has been a challenging task for mass spectrometry. In this study, we demonstrated that solid-substrate electrospray ionization mass spectrometry with nonpolar solvents such as n-hexane could allow detection of native proteins and protein complexes directly from raw biological samples. Mechanistic study revealed that the process involved rapid vaporization of the nonpolar solvent, temperature reduction of substrate surface, condensation of water from the ambient air, and spray ionization of the condensed water with analytes under the electric field...
April 3, 2018: Analytica Chimica Acta
S Kumbhani, T Longin, L M Wingen, C Kidd, V Perraud, B J Finlayson-Pitts
Real-time in situ mass spectrometry analysis of airborne particles is important in several applications, including exposure studies in ambient air, industrial settings, and assessing impacts on visibility and climate. However, obtaining molecular and 3D structural information is more challenging, especially for heterogeneous solid or semisolid particles. We report a study of extractive electrospray ionization mass spectrometry (EESI-MS) for the analysis of solid particles with an organic coating. The goal is to elucidate how much of the overall particle content is sampled, and determine the sensitivity of this technique to the surface layers...
January 11, 2018: Analytical Chemistry
Ramakrishna Itteboina, U Divya Madhuri, Partha Ghosal, Monica Kannan, Tapan Kumar Sau, Tatsuya Tsukuda, Shweta Bhardwaj
Developing efficient ways to control the nanocluster properties and synthesize atomically-precise metal nanoclusters are the foremost goals in the field of metal nanocluster research. In this article, we demonstrate that the direct synthesis of atomically-precise, hydrophilic metal nanoclusters as well as tuning of their properties can be achieved by an appropriate selection of reactants, binding ligand, and their proportions. Thus a facile, single-step method has been developed for the direct synthesis of Au18(SC2H4CO2H)14 nanocluster in an aqueous medium under ambient conditions...
January 9, 2018: Journal of Physical Chemistry. A
Hua Wang, Zhenghao Fei, Zhenxing Li, Rong Xing, Zhengming Liu, Yangyang Zhang, Hui Ding
An infrared (940nm) laser desorption coupled with corona beam ionization (LD-CBI) technique was developed for expanding the application of the ambient mass spectrometry (AMS). A black ceramic sample plate was employed to facilitate the non-resonance absorption of laser energy. Solution and powder samples were immobilized in the shallow depression on ceramic plate and desorbed precisely since there was not gas disturbing. The dimer ion (m/z 1216.51) of reserpine was detected without any matrix assistance. In comparison with similar APCI-related ambient technique, the upper mass rang of analyte was broadened significantly...
March 1, 2018: Talanta
Zhigang Luo, Jingjing He, Jiuming He, Lan Huang, Xiaowei Song, Xin Li, Zeper Abliz
Quantitative mass spectrometry imaging (MSI) is a robust approach that provides both quantitative and spatial information for drug candidates' research. However, because of complicated signal suppression and interference, acquiring accurate quantitative information from MSI data remains a challenge, especially for whole-body tissue sample. Ambient MSI techniques using spray-based ionization appear to be ideal for pharmaceutical quantitative MSI analysis. However, it is more challenging, as it involves almost no sample preparation and is more susceptible to ion suppression/enhancement...
March 1, 2018: Talanta
Chi-Wei Lee, Yu-Ying Chao, Jentaie Shiea, Jheng-Heng Shen, Hei-Hwa Lee, Bai-Hsiun Chen
A 25-year-old man suffered from consciousness change was sent to our emergency department by friends who reported that they were not sure what had happened to him. Physical examination revealed bilateral pupils dilatation, lethargy, slurred speech, and ataxia. Computer-aided tomographic scan of the brain revealed no definite evidence of intracranial lesions. Routine laboratory tests revealed total physiological turmoil. Despite immediate commencement of aggressive treatment, the patient's condition deteriorated long before the traditional drug screen provided an answer for the identities of the multiple drugs overdose...
December 20, 2017: American Journal of Emergency Medicine
Yaghoub Hajizadeh, Hakimeh Teiri, Shahrokh Nazmara, Iman Parseh
Exposure to volatile organic compounds (VOCs) can cause cancers in human. This study aimed to measure the concentration of four VOCs including benzene, styrene, ethylbenzene, and phenol in ambient air of a petrochemical complex in Iran. Also, their urinary metabolites including phenol, mandelic acid (MA), and phenylglyoxylic acid (PGA) in the workers were monitored. Urine samples were collected before and after the 8-h workshift according to the NIOSH methods. They were analyzed by a gas chromatograph coupled with a flame ionization detector (GC-FID)...
December 19, 2017: Environmental Science and Pollution Research International
Jae Young Kim, Eun Seok Seo, Hyunmin Kim, Ji-Won Park, Dong-Kwon Lim, Dae Won Moon
We report a high spatial resolution mass spectrometry (MS) system that allows us to image live hippocampal tissue slices under open-air atmospheric pressure (AP) and ambient temperature conditions at the subcellular level. The method is based on an efficient desorption process by femtosecond (fs) laser assisted with nanoparticles and a subsequent ionization step by applying nonthermal plasma, termed AP nanoparticle and plasma assisted laser desorption ionization (AP-nanoPALDI) MS method. Combining the AP-nanoPALDI with microscopic sample scanning, MS imaging with spatial resolution of 2...
December 13, 2017: Nature Communications
Craig A Stinson, Wenpeng Zhang, Yu Xia
Ozonolysis of alkene functional groups is a type of highly specific and effective chemical reaction, which has found increasing applications in structural analysis of unsaturated lipids via coupling with mass spectrometry (MS). In this work, we utilized a low-pressure mercury lamp (6 W) to initiate ozonolysis inside electrospray ionization (ESI) sources. By placing the lamp near a nanoESI emitter that partially transmits 185 nm ultraviolet (UV) emission from the lamp, dissolved dioxygen in the spray solution was converted into ozone, which subsequently cleaved the double bonds within fatty acyls of lipids...
December 12, 2017: Journal of the American Society for Mass Spectrometry
Swathy Jakka Ravindran, Ramesh Kumar, Amitava Srimany, Ligy Philip, Thalappil Pradeep
By direct analysis of water purification membranes using ambient ionization mass spectrometry, an attempt has been made to understand the molecular signatures of bacterial fouling. Membrane based purification methods are used extensively in water treatment and a major challenge for them is biofouling. The build-up of microbes and their extracellular polymeric matrix clog the membranes and reduce their efficiency. To understand the early stages of bacterial fouling on water purification membranes, we have used Desorption Electrospray Ionization Mass Spectrometry (DESI MS), where ion formation occurs in ambient conditions and the ionization event is surface sensitive...
December 6, 2017: Analytical Chemistry
Sharon Lefler, Roi Vizel, Ella Yeor, Eran Granot, Omri Heifler, Moria Kwiat, Vadim Krivitsky, Miguel Weil, Yuval E Yaish, Fernando Patolsky
Silicon-based photodetectors cannot distinguish between different wavelengths. Therefore, these detectors relay on color-specific filters to achieve color separation. Color filters add complexity to color sensitive device fabrication, and hinder miniaturization of such devices. Here we report an ultra-small (as small as ~20 nm by 300 nm), red-green-blue-violet (RGBV) filter-free spectrally-gated FET (SGFET) detectors. These photodetectors are based on organic-SiNW hybrid FET devices, capable of detecting specific visible wavelength spectrum with FWHM under 100 nm...
December 4, 2017: Nano Letters
Stephen T Ayrton, Gareth Rhys Jones, David Douce, Mike Morris, R Graham Cooks
Atmospheric pressure chemical ionization (APCI) in air or in nitrogen with just traces of oxygen is shown to yield regioselective oxidation, dehydrogenation and fragmentation of alkanes. Ozone is produced from ambient oxygen in-situ and is responsible for the observed ion chemistry, which includes partial oxidation to ketones and C-C cleavage to give aldehydes. The mechanism of oxidation is explored and relationships between ionic species produced from single alkanes is established. Unusually, dehydrogenation occurs via water losses...
November 28, 2017: Angewandte Chemie
Tijana Vasiljevic, German Augusto Gómez-Riós, Janusz Pawliszyn
The analysis of oral fluid (OF) and urine samples to detect recent drug consumption has garnered considerable attention as alternative and less invasive biological matrices. Indeed, several groups have demonstrated that efficiently combining microex-traction and ambient ionization technologies can facilitate the rapid determination of target compounds in such biofluids at trace levels (low or sub ng mL-1). However, there is still a need for biocompatible devices that can both be implemented for in-vivo sampling and easily interfaced with mass-spectrometry (MS) analyzers...
November 24, 2017: Analytical Chemistry
Rian L Griffiths, Klaudia I Kocurek, Helen J Cooper
Ambient surface mass spectrometry encompasses a broad range of sampling and ionization techniques. To date, only a small subset of these, based on liquid microjunction extraction, have proven suitable for intact protein analysis from thin tissue sections. Liquid extraction surface analysis shows particular promise for this application. Recently, a range of ion mobility spectrometry approaches have been coupled with ambient mass spectrometry. Improvements in signal-to-noise ratios, decreased chemical noise and separation of molecular classes have been described for the analysis of various biological substrates...
November 18, 2017: Current Opinion in Chemical Biology
Xiaoping Zhang, Konstantin Chingin, Dacai Zhong, Liping Luo, Vladimir Frankevich, Huanwen Chen
The chemical origin and biological role of distinct semen-like odor occasionally found in some flowers are very curious but remain scarcely studied. Here, we used direct ambient corona discharge ionization mass spectrometry (MS) to study the volatile chemical composition behind the semen-like odor emitted by the fresh flowers of Photinia serrulata, Castanopsis sclerophylla and Stemona japonica without any chemical pretreatment. Chemical identification was performed using high-resolution MS analysis in combination with tandem MS analysis and whenever possible was confirmed by the analysis of standard reference compounds...
November 8, 2017: Phytochemistry
Elizabeth A Crawford, Stefanie Gerbig, Bernhard Spengler, Dietrich A Volmer
Ambient ionization techniques are typically used to analyze samples in their native states with minimal or no sample pretreatment prior to mass spectrometric (MS) analysis. Desorption electrospray ionization (DESI) and direct analysis in real time (DART) were systematically investigated in this work for direct solid analysis of depolymerized lignin samples, with the goal of rapidly fingerprinting these samples, to efficiently characterize the subunits of this renewable energy source. High resolution MS was required for enhanced selectivity in this study due to the inherent structural complexity of lignin...
November 22, 2017: Analytica Chimica Acta
Daoiz Zamora, Mario Amo-Gonzalez, Marta Lanza, Gonzalo Fernandez De La Mora, Juan Fernandez de la Mora
The feasibility of detecting explosives in the atmosphere at concentrations as low as 0.01 ppq hinges on the poorly known question of what interfering species exist at these or higher concentrations. To clarify the issue, hundreds of samples of ambient air, either clean or loaded with explosives (from lightly contaminated environments) have been collected in fiberglass/stainless steel filters coated with Tenax-GR, thermally desorbed at variable temperature, and ionized with Cl- via secondary electrospray (SESI)...
November 9, 2017: Analytical Chemistry
Kang Li, Li Li, Bo Cui, Zhihui Gai, Qiuyue Li, Shumei Wang, Jun Yan, Bencheng Lin, Lei Tian, Huanliang Liu, Xiaohua Liu, Zhuge Xi
Epidemiological studies have revealed that ambient fine particulate matter (PM2.5) exposure is closely associated with autism spectrum disorder (ASD). However, there is a relative paucity of laboratory data to support this epidemic finding. In order to assess the relationship between PM2.5 exposure and ASD, neonatal male Sprague-Dawley (SD) rats were chosen and exposed to PM2.5 (2 or 20 mg/kg body weight, once a day) by intranasal instillation from postnatal day (PND) 8 to 22. It was found that when exposed to PM2...
November 7, 2017: Toxicological Sciences: An Official Journal of the Society of Toxicology
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