Biotage 04144 Union 1/4 x 1/8 with Knurled Nut and PFA Ferrules Pack of 3 Unions

The Biotage 04144 Reducing Union is a specialized fluidic connector designed for high-performance liquid chromatography (HPLC) and flash chromatography systems, specifically for transitioning between different tubing sizes. This union provides a secure, leak-proof bridge between 1/4-inch and 1/8-inch outer diameter (OD) tubing, a configuration often required when connecting larger solvent supply lines to the more precise delivery lines of a chromatography instrument. The body of the union is typically constructed from high-purity polymers or stainless steel to ensure chemical compatibility with a wide range of organic solvents and mobile phases used in purification workflows.

The technical performance of this assembly is defined by its knurled nut and PFA (perfluoroalkoxy) ferrule system. The knurled design of the nuts allows for "fingertight" installation, enabling users to create a high-pressure seal without the need for wrenches, which prevents over-tightening and extends the life of the fittings. The use of PFA for the ferrules is critical; as a high-performance fluoropolymer, PFA offers near-universal chemical resistance and is softer than the tubing, allowing it to deform slightly and "swage" onto the tube surface to create a dead-volume-free connection. This pack of 3 unions is a standard consumable set for maintaining Biotage flash systems, ensuring that fluid paths remain clean and pressurized during critical separations.