Abstract: A portable gas chromatograph assembly for detecting chemical species comprises a sample collector/injector for introducing a sample into the system, a cryogenically enhanced stationary phase focusing zone for reducing the band width of the introduced sample, one or more resistively heated conductive film clad, fused silica capillary gas chromatograph columns and associated support structure for separating the sample mixture into its individual components, column temperature control electronics, and a detector for registering the sample components.