Aviv Analytical

Comprehensive two dimensional GCxGC improves the separation of GC. However, it suffers from complexity and high cost of purchase and cooling gases. In addition, GCxGC-MS is perceived to be limited to time of flight MS due to the need of fast scan speed for its narrow peaks.

We developed a novel method and device named pulsed flow modulation (PFM) for obtaining GCxGC and GCxGC-MS with supersonic molecular beams based on the use of quadrupole mass analyzer (Supersonic GC-MS), and without any added gas flow rate.

Sample compounds which elute from the first GC column are temporarily stored for a few seconds in a fused silica transfer line and are pulsed periodically injected by ~25 ml/min He gas pulse into the second column while simultaneously temporarily stopping the first column flow. After the pulse, 20 ml/min He develops the chromatography in the second column for a few seconds. The PFM is a simple and reliable device that does not require any added gas. The injection time can be tuned, and it is easily compatible with the Aviv Analytical 5975-SMB Supersonic GC-MS with its quadrupole mass analyzer since the increased PFM flow rate is handled by the nozzle chamber differential pumping. Thus, PFM-GCxGC in combination with the Aviv Analytical 5975-SMB Supersonic GC-MS provides a unique combination of improved separation and mass spectral information.

1. M. Poliak, M. Kochman and A. Amirav "Pulsed Flow Modulation Comprehensive Two Dimensional Gas Chromatography" J. Chromatogr. A. 1186, 189-195 (2008).
2. M. Poliak, A. B. Fialkov and A. Amirav "Pulsed Flow Modulation Comprehensive Two-Dimensional Gas Chromatography Tandem Mass Spectrometry with Supersonic Molecular Beams" J. Chromatogr. A. 1210, 108-114 (2008).

The Aviv Analytical's pulsed flow modulation GCxGC is not yet a stand alone product but it can be provided as a custom made product in combination with our 5975-SMB. Please contact us to learn more on PFM-GCxGC and/or ask us for the PFM-GCxGC and GCxGC-MS papers.