TrisGlycine

TrisGlycine, commonly referred to as Tris-Glycine, is a buffer system used in biochemistry and molecular biology, most notably in electrophoresis. It combines Tris base (tris(hydroxymethyl)aminomethane) and glycine to create a medium that maintains pH while carrying current during gel-based separations.

The standard Tris-Glycine running buffer for polyacrylamide gel electrophoresis (SDS-PAGE) contains about 25 millimolar Tris and 192 millimolar glycine, with the pH adjusted to approximately 8.3 at room temperature. This composition provides a stable pH environment and a buffer-capacity that supports protein separation as the sample migrates through the gel matrix. Temperature can influence the exact pH, so buffers are typically prepared and used at a defined temperature or adjusted accordingly.

Applications of Tris-Glycine are predominantly in electrophoresis workflows. It is used as the running buffer in SDS-PAGE and in some native PAGE procedures, where it helps establish the electric field and facilitates protein separation by size. Variants of the buffer are also employed in transfer buffers for Western blotting, or in related staining and visualization steps, sometimes with additives such as methanol or glycerol to optimize performance.

Preparation and handling are straightforward: dissolve the specified amounts of Tris base and glycine in water, adjust the pH to about 8.3, and filter or sterilize as needed. The solution is typically prepared fresh or stored at standard refrigerated conditions. Safety considerations follow standard laboratory practices for handling common inorganic salts; Tris and glycine are irritants in concentrated form and should be used with appropriate PPE.