Bis-tris methane

Bis-tris is an abbreviation of the trivial name (Bis(2-hydroxyethyl)-imino-tris(hydroxymethyl)-methane) for 2-[Bis(2-hydroxyethyl)imino]-2-(hydroxymethyl)-1,3-propanediol. It is generally used as a buffering agent in biochemistry. Bis-tris is an organic tertiary amine with labile protons having a pKa of 6.46 at 25°C. It is an effective buffer between the pH 5.8 and 7.3.