First day at the Breath Summit (Loughborough, UK)! Honored for sharing this time with the Breath Research community. Do not miss Guillermo Vidal's talk on Monday at 16:35h. He will talk about Real-time breath analysis with SESI-HRMS and standardization.

Presentation of our Scietific poster on Real-time Breath analysis confounding variables and standardization strategies at ASMS-Atlanta 2019.

SESI and ESI (Electro-Spary Ionization) have been linked since the initial development of ESI. Fenn and colleagues already noted that gas-phase species in the counterflow gas were also ionized by the spray. Still today, the routine calibration of mass spectral data relies on ubiquitous plasticizes and other contaminants (i.e. polydimethylcyclosiloxanes, phthalates) that are ionized in regular ESI via Secondary Electrospray Ionization mechanisms.

Rising the humidity level of the gas introduced through the sample line accelerates the charge transfer reaction rate in Secondary Electrospray Ionization (SESI). It is hypothesized that larger clusters transfer their charge more efficiently than smaller clusters or even bare ions.

As you probably already know, current VOC MS analyzers can detect high volatile species, even when they are present in very low concentrations. For instance, in 2009 P. Spanel and D. Smith measured the concentration of ammonia, acetone, methanol, ethanol, and isoprene in human breath using Selected Ion Flow Tube Mass Spectrometry (SIFT-MS) [1] .

In the equilibrium, both Secondary Electro Spray Ionization (SESI) and Atmospheric Pressure Chemical Ionization (APCI) generate charged water clusters that act as charging agents. What are the differences bewtween these ionization techniques?

Breath Analysis performed with SUPER SESI is one of the topics of Thursday 22nd November (19.30) Beer for Science talk organised by Uciencia, the Publications and Scientific Dissemination Service of the University of Malaga.

Secondary Electro-Spray Ionization (SESI) uses a nano-electrospray that produces a cloud of charging ions. These ions ionize the vapor molecules that are in contact with the cloud.