Molar mass 121.14 g/mol Density 1.328 g/cm³ Melting point 175 °C | Formula C4H11NO3 Boiling point 219 °C Soluble in Water | |
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Appearance White crystalline powder IUPAC ID 2-Amino-2-hydroxymethyl-propane-1,3-diol |
Tris
Tris, or tris(hydroxymethyl)aminomethane, or THAM, is an organic compound with the formula (HOCH2)3CNH2. It is extensively used in biochemistry and molecular biology. In biochemistry, Tris is widely used as a component of buffer solutions, such as in TAE and TBE buffer, especially for solutions of nucleic acids. It contains a primary amine and thus undergoes the reactions associated with typical amines, e.g. condensations with aldehydes.
Contents
Buffering features
Tris has a pKa of 8.07 at 25 °C, which implies that the buffer has an effective pH range between 7.5 and 9.0.
Buffer details
Buffer inhibition
Preparation
Tris is prepared industrially by the exhaustive condensation of nitromethane with formaldehyde under basic conditions (i.e. repeated nitroaldol reactions) to produce the intermediate (HOCH2)3CNO2, which is subsequently hydrogenated to give the final product.
Uses
The useful buffer range for tris (7-9) coincides with the physiological pH typical of most living organisms. This, and its low cost, make tris one of the most common buffers in the biology/biochemistry laboratory. Tris is also used as a primary standard to standardize acid solutions for chemical analysis.
Tris is used to increase membrane permeability of cell membranes.
Medical
Tris (usually known as THAM in this context) is used as alternative to sodium bicarbonate in the treatment of metabolic acidosis.