HAWACH’s sample vial has excellent sealing performance, which can effectively avoid sample evaporation. The vial and the corresponding 11mm aluminum cap can be easily and quickly combined with the jaw capping tool. The vial can withstand heat and pressure, and can also be used for chemical reactions, especially for vials with thread openings, with white open caps and thick PTFE/silicone gaskets, which can be used as anhydrous and oxygen-free reaction vials.
To prevent contamination and avoid damage to the syringe and instrument, the correct sample vial septum selection is crucial. Here are some issues you should pay attention to:
At higher temperatures, the septa will degrade and cause sample contamination. Rubber septa are only stable below 90℃, so they are not suitable for high-temperature applications. Generally, PTFE-lined silicone rubber septa are the choice for various temperatures.
When the needle diameter is too large or the septum material cannot withstand multiple injections, scraps will be generated. At this time, the septum material will fall off into the sample vial and contaminate the sample. Here’s how to prevent scraps:
a. Select a PTFE-lined septum to prevent the septum material from entering the sample;
b. Make sure the needle is not damaged, consider using a side hole needle instead of a tapered needle;
c. Adopting pre-perforated septa can almost completely eliminate scraps;
d. For highly sensitive samples, PTFE-lined septum can act as a chemical-resistant barrier.
Resealing is an important factor to consider when choosing a septum. PTFE / red rubber septa are not recommended for multiple injections or samples that need to be stored for later analysis. PTFE/silicone/PTFE is always the choice when it takes longer between injections or when adding any type of standard sample.