Nov. 9th, 2023
Chromatography is a widely utilized analytical technique across industries such as pharmaceuticals, environmental analysis, and food testing. To ensure accurate and reliable results from chromatography setup, it is crucial to pay close attention to every detail - specifically septa used in vials for sealing. They help prevent contamination while protecting sample integrity. When selecting septa for use with your vials there are various factors you should take into consideration.
What Is a Septa?
A septum, also referred to as septa in its plural form, is a sealing barrier found inside chromatography vials and typically made of silicone or other elastomeric materials for optimal sealing purposes when needle injection occurs. Deciding upon a suitable septa type or configuration is key in guaranteeing its success in your analysis process.
7 Factors to Keep in Mind When Selecting Septa
Material: Septa are typically constructed out of silicone; however, other materials like polytetrafluoroethylene and butyl rubber may also be utilized depending on your sample and analytical method of choice. Silicone septa tend to be versatile and reliable while in more reactive or aggressive cases you may opt for either PTFE or butyl rubber septa instead.
Thickness: Septa come in various thicknesses, typically ranging from 0.5 mm to 3 mm. Thicker septa tend to be more durable and resistant to wear-and-tear, making them suitable for repeated injections; however, thinner septa are easier to puncture, which could prove essential when dealing with autosamplers that require precise needle penetration.
Composition: Septra come equipped with different materials that enhance their performance, such as those backed with PTFE for sealing and puncturing without risk of contamination. When selecting a septum composition that best matches your analytical requirements.
Pre-Slit Vs Non-Slit Septa: Septas can come either pre-slit or non-slit, with the former providing an easier needle penetration during sample injection; non-slit septa require needle puncturing on its own which may prove more challenging; pre-slit septa are preferred in most chromatography applications as they ensure an easy, reliable puncture that meets quality control standards.
Temperature Resistance: The specific requirements of your analysis may require septa with various temperature resistance levels to provide accurate analyses. When selecting your septa, be sure to choose something compatible with the method's temperature range to avoid degradation or failure during analytic procedures.
Compatibility With Cap: Before selecting septa for use on your chromatography vials, ensure they are compatible with the cap used to secure and create a leak-free seal. Septa should fit securely onto caps without creating leakage issues.
Application: When planning a chromatographic analysis, take note of your particular application's requirements. Different techniques like gas chromatography (GC), liquid chromatography (LC) and headspace analysis require different septa depending on their respective techniques; always consult manufacturer recommendations or industry best practices regarding specific septa that you will need for each technique.
At the heart of it all lies selecting the appropriate pre-slit septa for your chromatography vials - selecting one which meets material, thickness, composition and temperature resistance considerations is critical in ensuring successful analytical work. When making this choice it is vital that it maintains sample integrity by preventing contamination while producing accurate and reliable chromatographic results - take time and care with making this selection so it has maximum impact on achieving accurate and reliable chromatographic analyses! Choosing an incompatible septa may impact its integrity significantly and should be carefully considered prior to final selection!