Choosing the right injection port septum for your GC is not as simple as picking up any supplier’s catalog, looking at the temperature range stated for the septum, and assuming that it is made to the same specifications as any other septum. While it is true that there are a limited number of manufacturers of GC injection port septa, the specifications that are applied to one retail supplier are more likely not going to meet the same specifications of another. It would be true to say that only the design engineers of the specific GC’s injection port will know what specifications are needed for the best operation of the inlet as its intended design. Among other criteria, the septum must be of the correct dimensions and elastic density to cause sealing of the injection port in order to allow high-pressure carrier gas to be channeled to the GC column without allowing leaks. It must also do this in such a way to allow a relatively fragile syringe needle to pierce the disk in order to inject a sample into the inlet liner. While the disk is pierced with the needle, it must maintain a seal around the needle until it is eventually removed from the septum, and then the septum must be pliable enough to seal itself off to prevent the vaporous sample from escaping out through the needle’s hole. This self-occluding characteristic is absolutely vital in order to prevent the diffusion of air (containing oxygen) into the inlet. Allowing air into the carrier gas through insid
Agilent Premium Septa are designed specifically for Gas Chromatography (GC) inlet ports to ensure contaminant-free operation. Unlike standard cut or punched septa that may have an "hour-glass" shape leading to leaks and premature failure, these premium septa are injection molded into a uniform true disk shape with a conical dimple centering guide.
| Injection Temperature Range (BTO) | up to 400 °C |
|---|---|
| Injection Temperature Range (Advanced Green) | up to 350 °C |
| Packaging Environment | clean room environment |
It creates a nonstick surface that lowers background signal by preventing residual material from bleeding into the injection port and reduces conditioning time.
Allowing air containing oxygen to diffuse into the carrier gas through insidious leaks caused by poor sealing or septum shavings.