C. Berchtold, L. Meier, R. Steinhoff, R. Zenobi

Breath is considered to be an easily accessible matrix, whose chemical composition relates to compounds present in blood. Therefore many metabolites are expected in exhaled breath, which may be used in the future for the development of diagnostic methods. In this article, a new strategy to discriminate between exhaled endogenous metabolites and exhaled exogenous contaminants by direct high-resolution mass spectrometry is introduced.

Neil A. Devenport, Laura C. Sealey, Faisal H. Alruways, Daniel J. Weston, James C. Reynolds, and Colin S. Creaser.

A direct, ambient ionization method has been developed using atmospheric pressure thermal desorption–extractive electrospray–mass spectrometry (AP/TD-EESI-MS) for the detection of the genotoxic impurity (GTI) methyl p-toluenesulfonate (MTS) in a surrogate pharmaceutical matrix. A custom-made thermal desorption probe was used to the desorb and vaporize MTS from the solid state, by rapid heating to 200 °C then cooling to ambient temperature, with a cycle time of 6 min…

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

The metabolic phenotype varies widely due to external factors such as diet and gut microbiome composition, among others. Urine metabolite profiling studies have suggested that there are highly individual phenotypes that persist over extended periods of time. This hypothesis was tested by analyzing the exhaled breath of a group of subjects during nine days by mass spectrometry.

J. Zhu, H. D. Bean, J. Jiménez-Díaz, and J. E. Hill

Bacterial pneumonia is one of the leading causes of disease-related morbidity and mortality in the world, in part because the diagnostic tools for pneumonia are slow and ineffective. To improve the diagnosis success rates and treatment outcomes for bacterial lung infections, we are exploring the use of SESI-MS breath analysis as a rapid, noninvasive method for determining …

Christian Berchtold; Stefan Schmid; Lukas Meiera and Renato Zenobi.

γ-Hydroxybutyrate (GHB) and γ-butyrolactone (GBL) are used as “date rape drugs” since they cause catalepsy and memory loss. A new application of secondary electrospray ionization (SESI) mass spectrometry for in situ detection of GHB and GBL in drinks and body fluids is introduced.

J. Zhu, J. E. Hill

Escherichia coli O157:H7 (EC O157:H7), as well as its recently emerging non-O157 relatives, are a notorious group of pathogenic bacteria associated with foodborne outbreaks. In this study, we demonstrated that secondary electrospray ionization mass spectrometry (SESI-MS) could be a rapid and accurate detection technology for foodborne pathogens …

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

The development of noninvasive analytical techniques is of interest to the field of chronobiology, in order to reveal the human metabolome that seems to show temporal patterns and to predict internal body time. We report on the real-time mass spectrometric analysis of human breath as a potential method to be used in this field.

L. Meier, C. Berchtold, S. Schmid and R. Zenobi

In this study, we used secondary electrospray ionization mass spectrometry assisted by an ion funnel (IF) operating at ambient pressure to find compounds in the mass range of 100–500 m/z in online breath fingerprinting experiments. In low-resolution experiments conducted on an ion trap instrument, we found that pyridin is present in breath of individuals long after drinking coffee …

G. Vidal-de-Miguel, M. Macía, P. Pinacho, and J. Blanco

In secondary electrospray ionization (SESI) systems, gaseous analytes exposed to an elecrospray plume become ionized after charge is transferred from the charging electrosprayed particles to the sample species. Current SESI systems have shown a certain potential. However, their ionization efficiency is limited by …

Lukas Christian Meier

It has been known for years that breath analysis has the potential of becoming a powerful tool to acquire information on the health status of individuals. Using mass spectrometry (MS) for breath analysis would allow for the detection of hundreds of compounds simultaneously and even render real time (online) monitoring of the individual’s health status possible. Unfortunately, the efficient transfer of breath into mass spectrometers is difficult to achieve. Therefore, only very volatile organic compounds (VOCs) being present in breath at high concentrations have been measured so far. The work presented in this thesis intends to extend the range of compounds being detected in breath towards higher masses, less volatile and less concentrated compounds…

G. Vidal-de-Miguel, A. Herrero

In secondary electrospray ionization (SESI) systems, gaseous analytes exposed to an electrospray plume become ionized after charge is transferred from the charging electrosprayed particles (the charging agent) to the vapor species. Currently available SESI models are valid for simplified systems having only one type of electrosprayed species …

L. Meier, C. Berchtold, S. Schmid and R. Zenobi

In this study, we use an ion funnel (IF) at ambient pressure to enhance the sensitivity of secondary electrospray ionization (SESI). Atenolol, salbutamol and cocaine as test compounds are delivered to the SESI interface in the gas phase and are charged with three nano electrosprays …

P. M-L Sinues, E. Criado, G. Vidal-de-Miguel

The fact that electrosprays of pure solvents can efficiently ionize gas-phase analytes has been known for decades, although this method has not been widely exploited. With the advent of ambient mass spectrometry, this approach is becoming increasingly popular. However, the mechanism by which vapors become ionized remains largely unknown …

L. Meier, S. Schmid, C. Berchtold and R. Zenobi

In this study, we investigated how binary mixtures of compounds influence each other's signal intensity in electrospray ionization (ESI), extractive electrospray ionization (EESI) and secondary electrospray ionization (SESI) experiments. The experiments were conducted using a series of homologous primary amines (from 1-butyl to 1- decylamine) …

H. D. Bean, J. Zhu, J. E. Hill

Secondary electrospray ionization mass spectrometry (SESI-MS) is a method developed for the rapid detection of volatile compounds, without the need for sample pretreatment. The method was first described by Fenn and colleagues and has been applied to the detection of illicit drugs and explosives, the characterization of skin volatiles, and the analysis of breath.

Gerardo Gamez, Liang Zhu, Andreas Disko, Huanwen Chen, Vladimir Azov, Konstantin Chingin, Gunter Kramerb and Renato Zenobi

Valproic acid pharmacokinetics and ingestion in humans can be monitored through a novel biomarker in exhaled breath.

P. M-L Sinues, L. Zingaro, A. Finiguerra and S. Cristoni

A series of fatty acids among other compounds have recently been detected in breath in real time by secondary electrospray ionization mass spectrometry (SESI-MS). Our main aim in this work was to quantify their abundance in breath calibrating the system with standard vapors and extend the study to a control group for several days, both under fasting conditions and after sucrose intake.

C. Berchtold, L. Meier, R. Zenobi

Diagnosis by online breath analysis using mass spectrometry is challenging because of the low concentrations of pertinent compounds in breath. Here we investigate extractive electrospray ionization and atmospheric pressure chemical ionization for the detection of narcotics in breath.

J. Zhu, H. D. Bean, Y-M Kuo, and J. E. Hill

We propose a novel application of secondary electrospray ionization-mass spectrometry (SESI-MS) as a real-time clinical diagnostic tool for bacterial infection. It is known that volatile organic compounds (VOCs), produced in different combinations and quantities by bacteria as metabolites, generate characteristic odors for certain bacteria.

Liang Zhu, Zhong Hu, G. Gamez, Wai Siang Law, Huan Wen Chen, ShuiPing Yang, Konstantin Chingin, Roman M. Balabin, Rui Wang, TingTing Zhang, R. Zenobi

By gently bubbling nitrogen gas through beer, an effervescent beverage, both volatile and non-volatile compounds can be simultaneously sampled in the form of aerosol. This allows for fast (within seconds) fingerprinting by extractive electrospray ionization mass spectrometry (EESI-MS) in both negative and positive ion mode, without the need for any sample pre-treatment …