GC-MS with Cold EI and its Novel Enhancement Technologies

Aviv Amirav, Chemistry , Tel Aviv University, Tel Aviv, Israel
Alexander Fialkov, Chemistry , Tel Aviv University, Tel Aviv, Israel
Tal Alon, Chemistry , Tel Aviv University, Tel Aviv, Israel
Uri Keshet, Chemistry , Tel Aviv University, Tel Aviv, Israel
Svetlana Tsizin, Chemistry , Tel Aviv University, Tel Aviv, Israel

GC-MS with Cold EI is based on interfacing the GC and MS with supersonic molecular beams (SMB) along with electron ionization of vibrationally cold sample compounds in the SMB in a fly-through ion source (hence the name Cold EI). The Aviv Analytical 5977-SMB GC-MS with Cold EI provides enhanced molecular ions, significantly extended range of compounds amenable for analysis, much faster analysis and lower limits of detection particularly for difficult to analyze compounds.

However, in order to convert GC-MS with Cold EI into ideally suitable solutions for challenging applications we further developed and combined it with several additional novel enhancement technologies including: 

A. A unique low thermal mass fast GC enables sub one minute full analysis cycle time with short standard fused silica capillary columns.

B. Open Probe Fast GC-MS with Cold EI enables the provision of real time analysis with separation and library identification including with minimal or no sample preparation.

C. ChromatoProbe sample introduction device serves as an effective MS probe and as a manual thermal desorption unit for dirty samples analysis with minimal or no sample preparation and with enhanced sample integrity. 

D. Pulsed Flow Modulation GCxGC was combined with GC-MS with Cold EI for the combination of improved separation with best identification and the elimination of ion source peak tailing and second column peak fronting.

E. TAMI molecule identifier software was developed for improved sample identification with quadrupole mass analyzers. It combines improved mass accuracy with isotope abundance analysis for the provision of elemental formulae.

F. Electron ionization LC-MS was developed based on a minor modification of GC-MS with Cold EI. A dual GC-MS and EI-LC-MS system with mouse click mode conversion is under development.