An inlet splitter apparatus and method for introducing substantially unreacted linear aliquots of vaporized sample and carrier gas to the capillary column of a capillary gas chromatograph. An elongate body with separate but axially aligned injector and mixing chambers, an inert (glass) tubular liner interconnecting the separate chambers and having an inlet in the injector chamber and a baffled outlet in the mixing chamber, carrier gas injection means to introduce a stream of carrier gas through an annular passage between the elongate body and tubular liner to an inert core passage in the liner. A sample port and self-sealing septum to facilitate injection of an analysis sample to the inert liner core passage. Heating means (preheater and body heater) to vaporize the sample and pass an intermixed stream of vaporized sample and carrier gas through the inert core passage and baffled outlet of the liner. An expansion zone and metered discharge in the mixing chamber to facilitate a linear split of the sample through the inlet end of a capillary chromatograph column.
Optionally, it is preferred to increase the vaporization surface and mixing potential within the tubular liner and injection chamber by means of a packing or filler of very fine (100-120 mesh), inert material (glass beads).
The apparatus provides inert (glass) surfaces forming the pathway for the intermixed sample and carrier gas stream so that degradation of the sample by reaction with hot metallic or like surfaces is avoided. Turbulent intermixing within the baffled passageways of wholly inert (glass) components and filters assures that substantially unreacted linear aliquots of intermixed sample and carrier gas will pass to the capillary chromatograph column. The rate of flow of the carrier gas (at least 6 to 100 ml. per min.) is sufficient to insure that the apparatus is swept clean by carrier gas so that "band broadening" within the chromatograph column is avoided. Demountability of the apparatus permits removal and cleaning of the injector, liner, baffle and filter components to avoid chemical build-up and progressive sample degradation. Repetitive accuracy in capillary chromatographic analysis of very small substantially unreacted samples (e.g., 0.01 microliters) is thus assured.