March 3, 2009 - Entech Instruments announced the 7150 Headspace Preconcentrator, designed to recover thermally labile compounds for GC and GCMS applications, such as those containing sulfur, phosphorus and nitrogen. The 7150 is unique amongst sample concentrators in its ability to recover C2 to C25 compounds at PPM to sub-PPB levels, including labile compounds unable to survive strong adsorbents or a hot GC injector. A novel first-stage implements “Active SPME” allowing compounds from C12 to C25 to be trapped and desorbed quantitatively. The initial SPME stage eliminates the exposure of heavy VOCs and SVOCs to strong adsorbents, allowing their effective recovery and transmission to the GC.
Lighter, unretained compounds that are typically missed using classical, “diffusion-based SPME” are recovered utilizing a CO2 cooled Tenax trap. Cold trapping allows recovery of sulfur compounds, amines, and other thermally labile compounds that will not survive exposure to strong adsorbents.Dean Switching rather than rotary valves is used to control flows, eliminating absorptive surfaces and dead volume associated with the carryover of heavier and more polar compounds.
Moisture is removed prior to GCMS sample injection using direct vapor to solid phase cold trap dehydration that does not cause the loss of other headspace compounds.The combination of quantitative volume measurements and recovery of the widest range of GC compatible headspace-compounds, enables the true determination of aroma significant compounds during food and flavor testing. The 7150 system is compatible with the Entech 7405 and 7500A robotic autosamplers for R&D and production lab applications.Other applications for the instrument include environmental testing (air, water and soil), industrial hygiene, breath analysis, forensics, product testing, homeland security, package testing, and residual solvent testing in pharmaceuticals.