Tris(hydroxymethyl)aminomethane

White to off-white powder. Soluble in water (550mg/ml), methanol (26mg/ml), ethanol (14mg/ml), DMF (14mg/ml) or acetone (2mg/ml). Chemical. CAS: 77-86-1. Formula: C4H11NO3. MW: 121.14. Synthetic. A high quality buffer used in the range of physiological pH 7-9. Widely used as a biological buffer or as a component of buffer formulations. Tris has a pKa of 8.06 and is very useful in the biology and biochemistry lab because it has buffering capabilities in the range of the typical physiological pH of most living organisms (pH 7.0-9.0). Tris has been reported to interfere with the activity of a number of enzymes, it should therefore be used carefully when studying proteins.