Guillermo Vidal Guillermo Vidal

Secondary electrospray ionization proceeds via gas-phase chemical ionization

A. T. Rioseras, M. T. Gaugg and P. M-L Sinues

Our main goal was to gain further insights into the mechanism by which gas-phase analytes are ionized by interaction with plumes of electrospray solvents. We exposed target vapors to electrosprays of either water or deuterated water and mass analyzed them …

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Guillermo Vidal Guillermo Vidal

Use of Mass Spectrometric Vapor Analysis To Improve Canine Explosive Detection Efficiency

Ta-Hsuan Ong*, Ted Mendum, Geoff Geurtsen, Jude Kelley, Alla Ostrinskaya, Roderick Kunz

Canines remain the gold standard for explosives detection in many situations, and there is an ongoing desire for them to perform at the highest level. This goal requires canine training to be approached similarly to scientific sensor design. A sensitive, real-time (∼1 s) vapor analysis mass spectrometer was developed to provide tools, techniques, and knowledge to better understand, train, and utilize canines.

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Exhaled breath analysis by real-time Mass Spectrometry in patients with pulmonary fibrosis

P. M-L Sinues, Y. Nussbaumer Ochsner, M.T. Gaugg, L. Bregy, A. Engler, R. Zenobi, M. Kohler.

Idiopathic pulmonary fibrosis (IPF) is recognized as a distinct clinical disorder, however, the diagnosis method remains elusive. Metabolic profiling of biopsied tissue specimens has shown promise to gain insights into IPF pathogenesis. In view of this, the authors hypothesized that the analysis of exhaled metabolites may also provide further insights.

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Guillermo Vidal Guillermo Vidal

Targeted on-line breath analysis discriminates COPD patients vs. healthy controls and subjects suffering from asthma

Y. Nussbaumer-Ochsner, M.T. Gaugg, L. Bregy, A. Engler, S. A. Sophie, T. Gaisl, P. M-L Sinues, M. Kohler, R. Zenobi

Recently we found markers in exhaled breath discriminating patients with chronic obstructive pulmonary disease (COPD) from healthy controls using real-time mass spectrometry. The aim of this study was to validate the previously found disease specific metabolic profile of COPD in an independent cohort of patients suffering from chronic obstructive lung disease …

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Guillermo Vidal Guillermo Vidal

SESI-MS feasibility study with infants and young children for early detection of cystic fibrosis inflammation and infection

T. Bruderer, A. Baghdasaryan, J. Wyler, M. Kohler, R. Zenobi, A. Möller

Early and often subclinical pulmonary infection and pronounced neutrophilic inflammation are major contributors to CF-related morbidity. There is a causal relationship between high airway neutrophil elastase activity and the development of bronchiectasis. Early detection of disease and disease-associated .

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On-line breath analysis with secondary electrospray ionization discriminates between COPD patients with and without frequent exacerbations

M. T. Gaugg, Y. Nussbaumer-Ochsner, L. Bregy, A. Engler, N. Stebler, T. Bruderer, P. M-L Sinues, R. Zenobi, M. Kohler

The authors successfully identified metabolic patterns in exhaled breath, which discriminate COPD patients with and without frequent exacerbations. They propose that their findings correlate with the increased oxidative stress caused by elevated nitric oxide production in response to the pulmonary inflammation.

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Identification of Relatively High Molecular Weight Compounds in Human Breath Using Secondary Nano Electrospray Ionization Ultrahigh Resolution Mass Spectrometry

HUANG Lei, LI Xue, XU Meng, HUANG Zhengxu, ZHOU Zhen

Human breath contains thousands of volatile organic compounds (VOCs), which would be potentially helpful for studying disease diagnosis and environmental exposure. However, owing to limitations in current analytical methods, only the compounds with molecular weights <300 have been widely reported in exhaled human breath.

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二次纳流电喷雾电离耦合 超高分辨质谱检测人体呼出气中 相对高分子量化合物

黄 磊, 李 雪, 徐 萌, 黄正旭, 周 振

二次电喷雾电离源耦合超高分辨质谱(SESI⁃UHRMS)有望检出人体呼出气中分子量大于300 的相对 高分子量化合物, 这些化合物的发现将有助于更准确地理解呼出气中挥发性有机化合物(VOCs)的来源、产 生机制以及SESI 源电离机理, 更好地实现SESI⁃UHRMS 的转化应用. 本研究自组装nanoSESI 源(尚无商业产 品)耦合四极杆⁃静电场轨道阱质谱(最高质量分辨率1.2×10<sup>5</sup> ), 考察了该装置对健康人体呼出气中分子量 为300~500 化合物的检出情况. 结果表明, 所搭建的nanoSESI⁃UHRMS 装置检测人体呼出气的重现性好、灵 敏度高, 可检出数十种分子量为300~500 的化合物.

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Guillermo Vidal Guillermo Vidal

Rapid fingerprinting of grape volatile composition using SESI orbitrap MS: A preliminary study of grape ripening

R. R. Farrell, J. Fahrentrapp, D. Garcia Gomez, P. M-L Sinues, and R. Zenobi

Even though sugar and acidity measurements are the most common indices of grape maturity, it is well recognized that they provide only basic information related to wine quality. In this preliminary study te authors use SESI-MS to analyze VOCs directly from intact grapes without sample concentration.

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Gauging circadian variation in ketamine metabolism by real-time breath analysis

P. M-L Sinues, M. Kohler, S. A. Brown, R. Zenobi and R. Dallmann

The time-of-day of drug application is an important factor in maximizing efficacy and minimizing toxicity. Real-time in vivo mass spectrometric breath analysis and research of mice was deployed to investigate time-of-day variation in ketamine metabolism. Different production rates of ketamine metabolites were found in opposite circadian phases.

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Direct human breath analysis by secondary nano-electrospray ionization ultrahigh-resolution mass spectrometry: Importance of high mass resolution and mass accuracy

Xue Li, Lei Huang, Hui Zhu and Zhen Zhou.

RATIONALE: Direct mass spectrometry (MS)-based methods make it possible to monitor the molecular compositions of hundreds of volatile organic compounds (VOCs) in exhaled human breath in real time. Mass resolution and mass accuracy play important roles for direct MS analysis, especially for the low-concentration isobaric compounds in non-target research.

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Real-Time Quantification of Amino Acids in the Exhalome by SESI-MS: A Proof-of-Principle Study

D. García-Gómez, T. Gaisl, L. Bregy, A. Cremonesi, P. M-L Sinues, M. Kohler, and R. Zenobi

Amino acids are frequently determined in clinical chemistry. However, current analysis methods are time-consuming, invasive, and require sample preparation. The authors hypothesized that plasma concentrations of amino acids can be estimated by measuring their concentrations in exhaled breath.

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SESI-HRMS reveals tryptophan pathway metabolites in exhaled human breath

D. García-Gómez, T. Gaisl, L. Bregy, P. M-L Sinues, M. Kohler and R. Zenobi

Disorders in tryptophan metabolism result in diseases such as vitamin B6 responsive xanthurenic aciduria, hydroxy-kynureninuria, tryptophanuria and Hartnup disease. The authors hypotesized that breath analysis may reveal compounds that are metabolically linked to tryptophan. The mass range of detected metabolites reached up to 265 u, which is beyond the mass range limit (150–200 u) of competing breath research techniques such as PTR or SIFT-MS.

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Expanding metabolite coverage of real-time breath analysis by coupling a universal SESI source and a HRMS. A pilot study on tobacco smokers

M. T. Gaugg, D. Garcia Gomez, C. Barrios-Collado, G. Vidal-de-Miguel, M. Kohler, R. Zenobi and P. M-L Sinues

Coupling a SESI source and a HRMS (Orbitrap), the authors were able to identify exogenous compounds associated to smoking, as well as endogenous metabolites suggesting increased oxidative stress in smokers. According to the authors, most of these compounds correlated significantly with smoking frequency and allowed accurate discrimination of smokers and non-smokers.

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Breath Analysis Guillermo Vidal Breath Analysis Guillermo Vidal

Real-Time Chemical Analysis of E-Cigarette Aerosols by Means of Secondary Electrospray Ionization Mass Spectrometry

D. Garcia-Gomez, T. Gaisl, C. Barrios-Collado, Guillermo Vidal-de-Miguel, M. Kohler and R. Zenobi

Chemical analysis of aerosols collected from electronic cigarettes (ECs) has shown that these devices produce vapors that contain harmful and potentially harmful compounds. Conventional analytical methods used for the analysis of electronic cigarettes do not reflect the actual composition of the aerosols generated because they usually neglect the changes in the chemical composition that occur during the aerosol generation process and after collection.

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Capturing in Vivo Plant Metabolism by Real-Time Analysis of Low to High Molecular Weight Volatiles

C. Barrios-Collado, D. Garcia-Gomez, R. Zenobi, G. Vidal-de-Miguel, Alfredo J. Ibanez, and P. M-L Sinues

The authors document how hundreds of species can be tracked with an unparalleled time resolution of 2 min during day−night cycles. To further illustrate the capabilities of SESI-MS for volatile organic compounds (VOCs) analysis, they subjected the plant to mechanical damage and monitored its response.

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The Effect of CPAP Withdrawal on Exhaled Breath in Obstructive Sleep Apnea – A Randomized Controlled Trial

E. I Schwarz, P. M-L Sinues, L. Bregy, T. Gaisl, D. Garcia-Gomez, M. T. Gaugg, Y. Suter, N. Stebler, Y. Nussbaumer-Ochsner, K. E. Bloch, J. R. Stradling, R. Zenobi, M. Kohler

Patients with OSA effectively treated with CPAP were randomised to either withdraw treatment or continue CPAP for 2 weeks. Exhaled breath analysis and research by untargeted SESI-MS was performed at baseline and 2 weeks after randomisation. CPAP withdrawal led to a recurrence of OSA, which was accompanied by a significant change in 16 identified metabolites.

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