Advances in GC techniques can lead to higher injection port temperatures. At elevated temperatures, septa can stick to the injection port hardware or harden causing leaks which can lead to poor reproducibility. Septa coring is also a problem which results in debris entering the injector liner and possibly even the capillary column itself. Today's septa technology provides outstanding mechanical properties for repeated manual or autosampler injections, and chemical properties which give ideal low bleed characteristics for elevated temperature use. Hot tip: All septa are packed in cleaned glass bottles to maintain purity. Never handle septa with your fingers - the oils on your skin may contaminate the inlet. Always use tweezers when handling and installing septa.
