Caps & Closures

The cap and septum closing an autosampler vial are the last line of defense between your sample and the environment — and the first point of contact between your autosampler needle and the analytical flow path. A septum that cores, fragments, or fails to reseal after repeated needle penetrations introduces particulate contamination that blocks frits, damages injector components, and generates ghost peaks that compromise adjacent injections. Cap liners that are chemically incompatible with the sample solvent leach plasticizers and extractables into the matrix, adding background interference at exactly the concentration range where trace-level methods are most vulnerable. Selecting the correct cap format, liner material, and septum hardness for the application is as technically important as selecting the vial itself, and mismatches between cap and vial thread specification are among the most common sources of preventable leakage and evaporative loss in high-throughput sequences.

Ibis Scientific carries a comprehensive range of autosampler caps and closures covering every major vial format and closure style in use across modern chromatography laboratories. Our selection includes aluminum crimp caps in 8 mm, 11 mm, and 20 mm diameters, magnetic snap caps for tool-free closure, and screw-top caps in 9 mm, 10 mm, and 18 mm thread formats compatible with Agilent™, Waters™, Shimadzu™, Thermo Scientific™, and Perkin-Elmer™ autosampler platforms. Septum liner options span PTFE-faced silicone for general organic and aqueous applications, red PTFE-faced white silicone for USP and pharmaceutical methods, butyl rubber for headspace and volatile analysis, and bonded PTFE liners for aggressive solvent compatibility. Pre-slit and non-slit formats are available across the full liner range to match needle gauge and penetration force requirements. Contact Ibis Scientific for cross-reference assistance, matched vial and cap kits, or volume pricing on high-use closure programs.