Jérôme Kaeslin, Cedric Wüthrich, Stamatios Giannoukos, and Renato Zenobi

Secondary electrospray ionization (SESI) is a soft ionization method, which is important to avoid interference from in-source fragments and to simplify compound annotation. In this work, it is shown that SESI is softer than electrospray ionization (ESI), and therefore, SESI indeed qualifies as a soft ionization technique. However…

Jiayi Lan, Jérôme Kaeslin, Giorgia Greter, Renato Zenobi
Here, we show that besides ion suppression, ion competition in the C-trap of Orbitrap instruments is another important factor that influences sensitivity and reproducibility of SESI-MS. Instead of acquiring the full mass-to-charge ratio (m/z) range, acquisition of consecutive m/z windows to minimize the ion competition effect allows the detection of more features.

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.

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 …

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. …

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 …

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 …