Septa and Liners
Septa
CS silicone septa are high-quality septa for general use in gas chromatography. The 3 mm thick septa made of soft, transparent silicone are available in diameters from 9 mm to 18 mm.
Our CS-HT septa made of grey silicone have been optimized for standard applications at higher operating temperatures, are available in the same dimensions and offer higher temperature stability with low bleeding.
Center point guides the needle for easy penetration.
- Reduces the bending of the needle
- Precise shaping ensures an exact fit
- Packaged in glass jars for high purity
Premium septa are precision molded with a recess on the injection side to guide the syringe needle to the same location with every injection. The CenterGuide design requires less force during initial penetration for a smoother feel. Septum life can be extended in some applications by minimizing tearing and gouging.


BTO Septa
BTO septa are bleed- and temperature-optimized for the most demanding GC and GC-MS applications: They are the best GC septa we have tested. BTO septa are designed to extend the low bleed and excellent mechanical properties of premium GC septa to the highest temperature applications. They maintain remarkable softness and pierceability at high temperatures, with extremely low bleed, and have been optimized to reduce adhesion to the injection port.

Marathon Septa
These are advanced GC septa for use in autosamplers with significantly longer life. The Marathon septum typically achieves 400 injections without failure when used with a rounded tip needle (HP style) and an autosampler or needle guide. Now you can perform longer autosampler runs without fear of sample loss due to blowback from leaking carrier gas. The Marathon septum is also ideal for standard GC and GC-MS with manual injection.

Advanced Green 3 Septa
The CRS Advanced Green 3 septum has been developed to combine a significantly longer injection life, low bleeding and low adhesion to the injection port. The result is a septum that you can use for all your critical analyses.
Liners
In gas chromatography (GC), inlet liners play an important role in sample application into the GC system. They are located in the injector and serve to optimally introduce the sample into the gas chromatograph and ensure efficient separation of the analytes.
In the liner, the sample is evaporated and transferred to the column with as little decomposition and loss as possible. This is a critical step in gas chromatographic analysis, because:
- Decomposition of labile sample components, often catalyzed by active sites such as silanol groups on the liner, leads to artifacts. Active compounds such as amines can be irreversibly adsorbed on silanol groups on the liner, which also changes the sample composition. These effects can be avoided with our high-quality silanization processes, which result in very low residual silanol activity.
- When separating analytes with widely differing boiling ranges, discrimination effects can occur in which compounds with higher boiling points are evaporated significantly less effectively, again distorting the sample composition. This can be minimized by choosing liners with glass wool and/or tapers.
- The volume of the liner also plays an important role in the analysis. Aqueous samples in particular experience an enormous increase in volume during evaporation, for which the liner must be designed. If the vapor volume exceeds the volume of the liner, sample vapor escapes into the gas supply lines to the injector, where analytes condense and can lead to a high baseline and/or ghost peaks in subsequent analyses.
The choice of a suitable liner therefore has a significant influence on the efficiency and accuracy of your chromatographic process. For this reason, there is a wide variety of different liner geometries. Liners with more unusual geometries can be quite expensive, but do not have to be disposed of after use. With our exclusive liner regeneration service, used liners can be reused many times, saving the user a considerable amount of money and making the process much more sustainable than disposal.


