How to Choose the Right Chromatography Vial

Standard chromatography vial sizes include 8 x 40mm, 12 x 32mm, and 15 x 45mm. Robotic Arm Machines (R.A.M.) use a non-standard 9mm vial with a magnetic cap. For autosamplers, choose a vial designed for that specific brand.

Inserts can be used to decrease the capacity of the vial while maintaining the exterior dimensions. They are useful for smaller samples to ensure the correct amount of sample is aspirated from the vial. Inserts may be flat bottomed, conical (often with a plastic spring at the bottom), or pre-fused into the vial itself (sometimes called a micro vial). Make sure the insert that you choose will fit within the dimensions of the vile you have selected.

Chromatography vials typically have crimp, snap, or screw finishes. Closures may be pre-assembled with septa or the septa purchased separately. Vials with closures are also sometimes sold in pre-assembled sets.

Crimp top finishes are used with aluminum crimp seals to create a more permanent closure. Choose a flat finish or use a beveled finish for a tighter seal.

A snap finish accommodates a cap that is more easily applied and removed. Some vials have a finish that can be used with either crimp-top or snap closures.

Both snap and screw closures are usually made from plastic (polyethylene, PP, or a phenolic resin). They are available in a range of colors and sizes. The size of screw thread closures is typically expressed as two numbers that represent the diameter and the standard thread finish. For example, a closure size of 28-430 indicates a diameter of 28mm and a 430 GPI thread finish

Choose septa based on compatibility with your solvent. Most septa are faced with polytetrafluoroethylene (PTFE), but when that layer is punctured, the solvent may also come into contact with the underlying material.