Chromatography Vials & Caps
The following pages support Stratlab's .red® range of chromatography vials, caps and accessories. Products are summarised in the brochure below.
Our policy is to place vial and cap quality as the priority in what is a very competitive market.
Nearly all glass vials in the range are manufactured in Europe typically using Filolax®, high purity borosilicate glass produced by Schott.
.red® caps are all manufactured in the USA by one of the largest independent cap producers in the country. Our caps are identical to those sold by several of the largest chromatography instrument companies.
Septa material and combinations
Septa should be determined by the type of sample for analysis. There are 6 common types of liner manufactured in conjunction with vials that can be used inserted into crimp caps, screw caps and or snap caps.
The hardness of rubber can have influence on sealing. Another term for Durometer is Shore hardness. Shore A Durometer hardness measures the resistance of a material to indentation. The hardness gives an indication of the type of properties to expect from a material but is not always the indicator of performance.
The typical hardness for chromatography septa is Shore A 45, +/- 5, but can also be Shore A 35 +/- 5, or Shore A 50 +/- 5.
Septa used in chromatography almost always has a Fluoro-polymer material facing the sample, commonly Fluoro-polymer is PTFE
Septa Compatibility Post Injection
Poor = Post injection this septum will exhibit sample loss and deterioration
Fair = Post injection this septum will maintain integrity for a limited period of time with some deterioration
Good = Post injection this septum will maintain integrity for an extended period of time minor deterioration
Excellent = Post injection this septum will maintain integrity for high percentage of analytical sample analysis with absolute minimal deterioration
Septa Chemical Properties
Torque Tables for Screw Caps
There are many slight variations of vial thread although they are all commonly referred to as a ‘finish’ or GPI (Glass Packaging Institute) internal manufacturing standard. These are commonly described as 8-425, 13-425or 24-400. It is critical to marry correctly the container ‘finish’ to the correct cap size.
Closures are designated by their inside diameter in millimeters followed by a CMA (Closures Manufacturers Association) designation number. For example 8-425 closure identifies the cap as having an 8mm inside diameter and will fit a 425 finish container. The 9mm ‘short thread’ cap does not have a standardized description and needs careful marrying to specific vials.
Despite not having a standard description, the 9mm screw cap is prevalent in the industry and is the .red® standard. We do not offer 8-825 or 10mm screw caps and vials unless specifically requested.
As a basic guide application torque in Newton-metres should be about half the closures diameter in millimeters.
Polypropylene vials are sourced from various producers to compliment the range.