Tris(hydroxymethyl)aminomethane hydrochloride
[CAS# 1185-53-1]

Identification

• Classification: Chemical reagent >> Organic reagent >> Halogenated aliphatic hydrocarbon
• Name: Tris(hydroxymethyl)aminomethane hydrochloride
• Synonyms: 2-Amino-2-(hydroxymethyl)-1,3-propanediol hydrochloride; Tromethane hydrochloride; Trizma hydrochloride
• Molecular Formula: C₄H₁₁NO₃.HCl
• Molecular Weight: 157.59
• CAS Registry Number: 1185-53-1
• EC Number: 214-684-5
• SMILES: C(C(CO)(CO)N)O.Cl

Properties

• Melting point: 150-152 °C
• Water solubility: SOLUBLE

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P305+P351+P338

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Skin irritation	Skin Irrit.	2	H315
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2A	H319

Discovery and Applications

Tris-HCl, commonly known as Tris-HCl, is a derivative of the compound Tris introduced in the mid-20th century. Tris, short for tris-hydroxymethylaminomethane, was discovered during the search for effective biological buffers. Its hydrochloride, Tris-HCl, was developed to provide improved solubility and stability, becoming an important tool for maintaining pH in biochemical and molecular biology applications.

The molecular formula of Tris-HCl is C4H11NO3·HCl. It consists of one Tris molecule (tris-hydroxymethylaminomethane) bound to hydrochloric acid. This structure provides Tris-HCl with buffering capacity, which is particularly effective in the pH range of 7.0 to 9.0. The addition of the hydrochloric acid group enhances its solubility in water, making it a top choice for many laboratory applications.

Tris-HCl is widely used as a buffer in a variety of biochemical and molecular biology experiments. Its stability and compatibility with a range of biomolecules make it ideal for maintaining pH in enzyme reactions, nucleic acid purification, and cell culture media. It is a key component in the preparation of solutions such as Tris-buffered saline (TBS) and Tris-acetate-EDTA (TAE) buffers, which are commonly used in electrophoresis and other molecular biology techniques.

In electrophoresis, Tris-HCl is used to prepare buffer solutions that maintain a stable pH during nucleic acid and protein separations. For example, in SDS-PAGE (sodium dodecyl sulfate-polyacrylamide gel electrophoresis), Tris-HCl buffer helps ensure consistent migration of proteins, allowing accurate determination of their molecular weights.

Tris-HCl is used in protein purification protocols such as ion exchange chromatography and affinity chromatography. Its buffering capacity helps maintain the pH of the solution, ensuring that proteins remain in their native state, which is critical for their stability and functionality during purification.

Tris-HCl is used in cell culture media to maintain pH, providing a stable environment for the growth and maintenance of various cell lines. Its buffering action ensures that the physiological conditions required for cell proliferation and differentiation are maintained.

Tris-HCl is an important component in the formulation of diagnostic reagents, especially those that require a stable pH. Its nontoxic nature and compatibility with biological systems make it suitable for use in diagnostic tests and kits.

References

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2025. CRISPR-Mediated Viral Gene Knockout to Investigate Viral Evasion of Antiviral Innate Immunity. Methods in molecular biology (Clifton, N.J.), 2854.
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2025. Investigation of Protein Lysine Acetylation in Antiviral Innate Immunity. Methods in molecular biology (Clifton, N.J.), 2854.
DOI: 10.1007/978-1-0716-4108-8_15