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.

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.

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１.２×1０^５ ）， 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．

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.

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.

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.

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.

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.

G. Trecate, P. M-L Sinues & R. Orlandi

Breast cancer screening and presurgical diagnosis are currently based on mammography, ultrasound and more sensitive imaging technologies; however, noninvasive biomarkers represent both a challenge and an opportunity for early detection of cancer …

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.

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.

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.

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.

Matthew J. Aernecke, Ted Mendum, Geoff Geurtsen, Alla Ostrinskaya, Roderick R. Kunz*

A rapid method for vapor pressure measurement was developed and used to derive the vapor pressure curve of the thermally labile peroxide-based explosive.

L. Bregy, A. R. Müggler, P. M-L Sinues, D. García-Gómez, Y. Suter, G. N. Belibasakis, M. Kohler, P. R. Schmidlin, Renato Zenobi

The detection of bacterial-specific volatile metabolites may be a valuable tool to predict infection. Here we applied a real-time mass spectrometric technique to investigate differences in volatile metabolic profiles of oral bacteria that cause periodontitis. We coupled a secondary electrospray ionization (SESI) source to a commercial high-resolution mass spectrometer …

P. M-L Sinues, Elena Landoni, Rosalba Miceli, Vincenza F. Dibari, Matteo Dugo, Roberto Agresti, Elda Tagliabue, Simone Cristoni, Rosaria Orlandi.

SESI–MS produces high-dimensional data of quality comparable to gene expression analysis output. This prompted the authors to use methods originally developed for gene expression data in analyzing SESI–MS breathprints.

D. García-Gómez, L. Bregy, Y. Nussbaumer-Ochsner, T. Gaisl, M. Kohler, and R. Zenobi

2-Subtituted benzothiazoles are widely used industrial chemicals whose occurrence in environmental samples has been shown to be ubiquitous. However, knowledge about human exposure to these compounds and their excretion route is still scarce. Here, we demonstrate for the first time the detection of benzothiazole derivatives in exhaled breath.

C. Barrios-Collado, G. Vidal-de-Miguel, P. M-L Sinues

The process by which ambient vapors are ionized upon interaction with electrosprays is not fully under-stood, compromising its optimization and widespread use. In this work we evaluated the different scales associated with the processes involved in secondary electrospray ionization (SESI) and developed a new numerical method …

D. García-Gómez, L. Bregy, C. Barrios-Collado, G. Vidal-de-Miguel and R. Zenobi

The identification of chemical compounds in exhaled human breath is promising in the search for new biomakers of diseases. However, the analytical techniques used nowadays are not capable of achieving a robust identification, especially in real-time analysis.

Alex R. Hill, Mark Edgar, Maria Chatzigeorgiou, James C. Reynolds, Paul F. Kelly* and Colin S. Creaser*

The complexation of triacetone triperoxide (TATP) with a range of alkali metals has been studied by electrospray ionisation mass spectrometry to yield [M + Cat]+ ions for all of the alkali metals. The formation of [2TATP + Li + LiX]+ (X = Br, Cl) sandwich complexes was also observed. Collision cross-sections for the lithium-containing complexes of TATP were measured by travelling wave ion mobility spectrometry mass spectrometry and compared well with computationally determined structures. Extractive electrospray ionisation (EESI) using a lithium-doped electrospray is demonstrated for the detection of TATP vapours desorbed from a metal surface. The limit of detection for EESI was shown to be 20 ng using the [TATP + Li]+ ion.