Tris

From Free net encyclopedia

Template:Wikify-date

This article is about a chemical. For the baseball player, see Tris Speaker.

Tris is an abbreviation or trivial name for 2-amino-2-hydroxymethyl-1,3-propanediol. It is widely used as a buffer in biochemistry. Tris is an organic polyamine used to control the pH in range b/w 6.5 and 9.7. With a pKa of 8.30 (at 20 °C; this declines approximately 0.03 units per degree Celsius rise in temperature), tris is an effective buffer over the pH range of approximately 7.5 to 9.0.

Tris is often used when working with nucleic acids.

The name tris arises from the trivial name trishydroxymethylaminomethane. While it is nonsystematic, it provides an easy way to grasp the structure of the compound.

Contents 1 Synonyms 2 Usage 3 Identification 4 Properties

Synonyms

Synonyms for tris include: TRIS; Tris base; Tris buffer; Tris, free base; Trometamol; Tromethamine; Tromethane; Transmine; THAM; Trizma; Trizma base; Tris(hydroxymethyl)methylamine; 2-amino-2-hydroxymethylpropanediol.

Usage

Tris is used as an intermediate for the preparation of surface active agents, vulcanization accelerators, and pharmaceuticals, and used as a titrimetric standard.

Identification

• CAS NO: 77-86-1
• Molecular formula: (HOCH₂)₃CNH₂
• Molecular weight: 121.13624
• H.S. Code: 29221990

Properties

• Physical state: white crystalline powder
• Assay: 99.9% min
• Melting point: 168 to 172 °C
• Boiling point: 219 to 220 °C
• Loss on drying: ≤0.2%
• ASH: ≤0.05%
• pH(0.1 mol/L, 25 °C): 10.0-10.8
• Insoluble in water: ≤0.01%
• ABS (260 nm): ≤0.2
• Heavy metals (as Pb): ≤5 ppm
• Fe: ≤5 ppm
• SO₄²⁺: ≤5 ppm
• Cl: ≤5 ppmde:Tris