Application and preparation of Tris buffer

Details:

Buffer solution is an aqueous solution containing weak acid and its conjugated base. Due to the chemical properties of buffer solution, even if the substance changes chemically, The buffer can also change its pH value (acidity) is kept at an almost constant level. Buffer naturally exists in plasma, which keeps the pH value of blood between 7.35-7.45. In organic systems, natural buffer keeps the pH value at a consistent level. However, in the process of biological research, the pH value must be kept constant through buffer. There are many kinds of buffers, and Tris buffer is one of the commonly used biological buffers 。

Tris powder

What is Tris buffer

Tris is three The abbreviation of (hydroxymethyl) aminomethane, which is a compound commonly used in salt water, because it is isotonic and non-toxic, with pKa of 8.1 and pH value between 7 and 9. Therefore, Tris buffer solution is also commonly used in a series of chemical analysis and biological research, including DNA extraction. It is important to know that the pH value in Tris buffer solution changes with solution temperature.

How to prepare Tris buffer

The preparation of Tris buffer is very simple. Only the following materials are prepared

● tris (hydroxymethyl) aminomethane (Tris)

● distilled deionized water

● hydrochloric acid

step

1. First, determine the concentration (molar concentration) and volume of the tris buffer you want to make. For example, the tris buffer for normal saline ranges from 10 to 100 mm. According to the experimental requirements, calculate the number of moles of Tris required by multiplying the molar concentration of the buffer by the volume of the buffer being made. (moles of Tris = mol / L x L)

2. Next, determine how many grams this is by multiplying the number of moles by the molecular weight of tris (121.14 g / mol). The number of grams of Tris = (mole) x (121.14 g / mol)

3. Dissolve Tris in distilled deionized water to 1 / 3 to 1 / 2 of the required final volume.

4. Mix in HCl (e.g. 1m HCl) until the pH meter provides the required pH for your Tris buffer solution.

5. Dilute the buffer with water to reach the required final solution amount.