TRIS AMINO (tromethamine; 2-amino-2-hydroxymethyl-1,3-propanediol) is a four-carbon compound containing both hydroxyl and amine functional groups. The most notable uses of tromethamine are in the pH buffering of enzymes for both biotechnology and industrial applications, and in the purification of biological molecules, such as monoclonal antibodies, recombinant proteins and insulin for medical applications. The CAS # is 77-86-1.