Open Probe Fast GC-MS: MS Probe with Separation

Uri Keshet, School of Chemistry, Tel Aviv University, Tel Aviv, Israel
Alexander B. Fialkov, School of Chemistry, Tel Aviv University, Tel Aviv, Israel
Tal Alon, School of Chemistry, Tel Aviv University, Tel Aviv, Israel
Aviv Amirav, School of Chemistry, Tel Aviv University, Tel Aviv, Israel

A novel (US, Israel and Japan Patents) instrument and method for real time analysis with separation were developed by combining an open probe inlet with a low thermal mass (LTM) ultra-fast gas chromatograph (GC) and a mass spectrometer (MS) of GC-MS. The Open Probe is based on a vaporization oven that is open to room air while having helium purge flow protection to eliminate air leakage into the oven and MS ion source. 

Sample introduction into the Open Probe is done by touching the sample, pushing the sample holder into the open probe oven for its thermal vaporization and having the results in 20-30 s.

The Open Probe is mounted onto the LTM fast GC that is coupled either with a standard Agilent 5977 MSD or the Aviv Analytical 5977-SMB GC-MS with Cold EI, for obtaining in-vacuum electron ionization followed by quadrupole based mass analysis. Unlike DART, DESI and other related ambient ionization techniques, Open Probe fast GC-MS provides real time analysis in combination with GC separation, library identification (i.e. NIST), absence of ion suppression effects and uniform electron ionization response for improved quantitation. Furthermore, due to the fast GC separation it can be effectively used with the simple and low cost unit resolution mass spectrometer of GC-MS.

The operation of the Open Probe fast GC-MS will be demonstrated in a 3 minutes video that will show its operation in the 30 seconds analysis of Tetrahydrocannabinol (THC) and  Canabinol in Cannabis flower (including their separation and NIST library identification) plus in the 20 s separation time and 30 s full analysis cycle time of heroin in its street drug powder. Several other forensic and general applications will be demonstrated including trace TNT on human hand.