| What is a Drilled Uniliner® inlet liner?  The Drilled Uniliner® was designed and developed specifically for making direct injections in an Agilent GC equipped with electronic pressure control (EPC). A hole in the wall of the liner, near the inlet end or the outlet end, equalizes pressure and makes the liner compatible with EPC. The pneumatics for EPC in the Agilent GC consist of two pressure sensors, one upstream from the injector and one downstream from the injector, at the split vent. When a standard Uniliner® inlet liner is used for direct injection, it is sealed to the analytical column. Consequently, there is no downstream flow of carrier gas to the pressure sensor at the split vent. A pressure difference between the two sensors is detected and the upstream sensor overcompensates, causing a high pressure malfunction and shutdown of the GC. The Drilled Uniliner® allows a portion of the carrier gas to escape from the liner and equalize the pressure at the two sensors. The Drilled Uniliner® requires no software or hardware modifications, or flow adjustments. For optimum performance we advise that the purge be kept on and a very low split flow (e.g., 3-5mL/min.) be used. A Drilled Uniliner® also can be used for making splitless injections in an Agilent 5890 or 6890 GC. Liners for splitless injection typically are glass tubes, and are often packed with glass wool or fused silica to facilitate vaporization and trap non-volatile residue. But these designs are prone to drawbacks: potential adsorption and/or decomposition of active compounds on the packing material, and sample discrimination. A Drilled Uniliner® eliminates these problems. For more information request free literature, catalog numbers 59125, 59324, and 59487. | 
