Bis-tris methane

Bis-tris methane is a buffering agent used in biochemistry and molecular biology that has the chemical formula C_8H_19NO_5. It is also known by its systematic name, 2,2-bis(hydroxymethyl)-2,2',2-nitrilotriethanol. This compound is often used in the preparation of buffer solutions in biochemistry and molecular biology experiments, particularly in the pH range of 5.8 to 7.2. Bis-tris methane is favored for its minimal metal ion binding, low UV absorbance, and stability over a wide range of temperatures and concentrations.

Properties

Bis-tris methane is a zwitterionic buffer, meaning it has both positive and negative charges, which allows it to maintain a stable pH when either acids or bases are added. This property is crucial for maintaining the stability of the biochemical environment in experiments. The compound has a pKa of 6.46 at 25°C, making it an effective buffer around physiological pH.

Applications

In the field of biochemistry, bis-tris methane is commonly used in the preparation of buffer solutions for protein purification, nucleic acid isolation, and other molecular biology techniques. It is particularly useful in the electrophoresis of biological molecules, including both DNA and protein electrophoresis. Its buffering capacity is also exploited in cell culture media and in the formulation of reagents for PCR amplification.

Preparation and Usage

To prepare a bis-tris methane buffer, the compound is dissolved in water, and the pH is adjusted to the desired value using hydrochloric acid or sodium hydroxide. The concentration of bis-tris methane in a buffer solution can vary depending on the specific requirements of the experiment but typically ranges from 5 mM to 50 mM.

Safety and Handling

Bis-tris methane is generally considered safe for laboratory use, but it should be handled with care. As with all chemical reagents, it is advisable to wear appropriate personal protective equipment, such as gloves and goggles, and to work in a well-ventilated area. Material Safety Data Sheets (MSDS) should be consulted for detailed information on safety, handling, and disposal.

Environmental Impact

While bis-tris methane is not known to be particularly hazardous to the environment, it is important to follow all regulatory guidelines for disposal. This includes not disposing of large quantities in the sink and instead following institutional protocols for chemical waste disposal.

See Also

• Buffer solution
• Zwitterion
• Electrophoresis
• Molecular biology