Introducing the New Electron Impact Ionization Source Design for GC-MS

John Upton, Gas Chromatography Mass Spectrometry, Agilent Technologies, Stockport, UK

There is a continued drive within the analytical industry to deliver lower and lower detection limits. Having designed GC-MS systems that deliver very little noise, by virtue of instrument design and/or operational mode, the next step is a redesign of an electron impact source to secure both improved signal to noise, and from a practical point of view, an improvement to the calulated Instrument Detection Limit, IDL.

This presentation outlines the principles of the new source design which, compared to other designs, is able to increase between 10 and 20 fold the number of ions produced from a given number of neutral species entering the source region. The increase in ion numbers improves the relative ion statistics which in turn improves  the detection limit of the system. The spectra produced are classical 70eV spectra, so no adjustment is needed in relation to spectral interpretation or methodology.

The benefts of such an improvement to analytical sensitivity are described by practical examples. Likewise, the further benefits of having a  system delivering such a benchmark shift in performance are also explained in terms of system robustness, speed of laboratory workflow and significant the cost per reductions for many laboratories.