Whenever coned ports are used to make a connection, it is important to always take into account the diameter of the tubing pocket at the base of the port. Frequently, there is a need to connect smaller, capillary tubing into coned ports not originally designed for that size – and if this is not done properly, dead volume, mixing, band broadening and over-pressurization can result.
One of the best ways to adapt a port to being able to use capillary tubing is through the use of tubing sleeves. Tubing sleeves are ideal because they have an outer diameter that matches the tubing pocket in the receiving ports and they have an inner diameter that is very close in size to the capillary tubing being used. Also, because the sleeve is not an integral part of the ferrule, the sleeved tubing can adjust to various port depths, assuring a good connection with minimal dead volume.
Please Note: For best performance, it is recommended that you choose a tubing sleeve with an inner diameter that is .001” - .002” (25-50µm) larger than the outer diameter of your capillary tubing. This allows for easy insertion of the tubing while minimizing any potential dead volume that may result from the connection.
Analytical Instrumentation, In Vitro Diagnostics, Biotechnology, Laboratory