A novel direct sample introduction (DSI) device is described, based on sample introduction in a disposable mini-vial (test tube) inside the existing gas chromatography (GC) injector. This DSI device effectively transforms a conventional GC injector, followed by a short capillary column, into a very cost-effective alternative to the standard direct insertion probe and enables a continuous sample flux at the mass spectrometer ion source for mass spectrometry (MS) and MS-MS studies. This same device also enables direct introduction of dirty samples for GC and GC-MS analysis. The dirty sample introduction is based on the thermal extraction of semi-volatile sample compounds inside the GC injector, while the non-volatile residue is retained in the sample vial that is disposed of after the analysis. The major capabilities of this new DSI device are demonstrated and its various features are discussed.
- Direct sample introduction
- Extract-free supersonic molecular beams