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.

Xue Li, P. M-L Sinues, R. Dallmann, L. Bregy, M.Hollmén, S. Proulx, S. A. Brown, M. Detmar, M. Kohler, and R. Zenobi

Noninvasive, real-time pharmacokinetic (PK) monitoring of ketamine, propofol, and valproic acid, and their metabolites was achieved in mice, using secondary electrospray ionization and high-resolution mass spectrometry. The PK profile of a drug influences its efficacy and toxicity because it determines exposure time and levels …

H. D. Bean, T. R. Mellors, J. Zhu and J. E. Hill

A number of direct injection mass spectrometry methods that can sample foods nondestructively and without sample preparation are being developed with applications ranging from the rapid assessment of food safety to the verification of protected designations of origin. In this pilot study, SESI-MS in positive and negative-ion modes was used to …

D. García-Gómez, P. M.-L. Sinues, C. Barrios-Collado, G. Vidal-de Miguel, M. Gaugg, and R. Zenobi

In recent years, breath analysis in real time has become a noninvasive alternative for the diagnosis of diseases and for molecular fingerprinting of exhaled breath. However, the techniques used lack the capabilities for proper identification of the compounds found in the exhalome.

P. M-L Sinues, L. Tarokh, Xue Li, M. Kohler, S. A. Brown, R. Zenobi, R. Dallmann

Circadian clocks play a significant role in the correct timing of physiological metabolism, and clock disruption might lead to pathological changes of metabolism. One interesting method to assess the current state of metabolism is metabolomics. Metabolomics tries to capture the entirety of small molecules, i.e. the building blocks of metabolism, in a given matrix …

J-C Wolf, M. Schaer, P. Siegenthaler, R. Zenobi

A novel active capillary dielectric barrier discharge plasma ionization (DBDI) technique for mass spectrometry is applied to the direct detection of thirteen chemical warfare related compounds, including sarin, and compared to secondary electrospray ionization (SESI) in terms of selectivity and sensitivity.

J-C Wolf, M. Schaer, P. Siegenthaler, R. Zenobi

A novel active capillary dielectric barrier discharge plasma ionization (DBDI) technique for mass spectrometry is applied to the direct detection of thirteen chemical warfare related compounds, including sarin, and compared to secondary electrospray ionization (SESI) in terms of selectivity and sensitivity. The investigated compounds include an intact chemical warfare agent and structurally related molecules, hydrolysis products and/or precursors of highly toxic nerve (G-series, V-series and "new" nerve agents), blistering and incapacitating warfare agents. …

James C Reynolds, Modupe A Jimoh, Cristina Guallar-Hoyas, Colin S Creaser, Salman Siddiqui and C L Paul Thomas

A two-stage thermal desorption/secondary electrospray ionization/time-of-flight mass spectrometry for faster targeted breath profiling has been studied. A new secondary electrospray ionization (SESI) source was devised to constrain the thermal desorption plume and promote efficient mixing in the ionization region. Further, a chromatographic preseparation stage was introduced to suppress interferences from siloxanes associated with thermal desorption profiles of exhaled breath samples…

Jingjing He, P. M-L Sinues, M. Hollmén, Xue Li, M. Detmar & R. Zenobi

There is increasing interest in the development of noninvasive diagnostic methods for early cancer detection, to improve the survival rate and quality of life of cancer patients. Identification of volatile metabolic compounds may provide an approach for noninvasive early diagnosis of malignant diseases.

Helen J. Martin,a James C. Reynolds,a Svetlana Riazanskaiab and C. L. Paul Thomas*a

The non-invasive nature of volatile organic compound (VOC) sampling from skin makes this a priority in the development of new screening and diagnostic assays. Evaluation of recent literature highlights the tension between the analytical utility of ambient ionisation approaches for skin profiling and the practicality of undertaking larger campaigns (higher statistical power), or undertaking research in remote locations. This study describes how VOC may be sampled from skin and recovered from a polydimethylsilicone sampling coupon and analysed by thermal desorption (TD) interfaced to secondary electrospray ionisation (SESI) time-of-flight mass spectrometry (MS) for the high throughput screening of volatile fatty acids (VFAs) from human skin…

C. Ballabio, S. Cristoni, G. Puccio, M. Kohler, M. R. Sala, P. Brambilla, P. M-L Sinues

Blood cultures are routine tests to determine whether micro-organisms have entered the patient’s bloodstream. Automated systems, based on the detection of CO2 increase in the culture media, have considerably improved the screening efficiency for the detection of bacteria. However, further identification of bacteria still requires time consuming culturing procedures.

P. M-L Sinues, L. Meier, C. Berchtold, M.Ivanov, N. Sievi, G. Camen, M. Kohler, R. Zenobi

Background: It has been suggested that exhaled breath contains relevant information on health status. Objectives: We hypothesized that a novel mass spectrometry (MS) technique to analyze breath in real time could be useful to differentiate breathprints from chronic obstructive pulmonary disease (COPD) patients and controls (smokers and nonsmokers) …

Neil A. Devenport, Daniel J. Blenkhorn, Daniel J. Weston, James C. Reynolds, and Colin S. Creaser

A direct, ambient ionization method has been developed for the determination of creatinine in urine that combines derivatization and thermal desorption with extractive electrospray ionization and ion mobility-mass spectrometry. The volatility of creatinine was enhanced by a rapid on-probe aqueous acylation reaction, using a custom-made thermal desorption probe, allowing thermal desorption and ionization of the monoacylated derivative..

P. M-L Sinues, R. Zenobi, M. Kohler

Investigations on breath analysis have provided preliminary data on its potential in the noninvasive diagnosis of lung diseases. Although the conventional comparisons of exhaled breath in study populations (ie, diseased vs healthy) may help to identify patients with various lung diseases, we believe that the analysis of exhaled breath holds promise beyond this scenario …

J. Zhu, J. Jimenez-Díaz, H. D. Bean, N. A. Daphtary, M. I. Aliyeva, L. K. A. Lundblad and J. E. Hill

Before breath-based diagnostics for lung infections can be implemented in the clinic, it is necessary to understand how the breath volatiles change during the course of infection, and ideally, to identify a core set of breath markers that can be used to diagnose the pathogen at any point during the infection …