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A buffer used to denature proteins incudes the following components: 25 mM Tris-

ID: 186118 • Letter: A

Question

A buffer used to denature proteins incudes the following components:

25 mM Tris-HCl, pH 8.2

8 M urea

200 mM glycine

10 mM b-mercaptoethanol (BME)

250 mM NaCl

In the lab you have a 1 M solution of Tris buffer at pH 7.0, a bottle of BME at 14.3 M and solid urea, glycine, and NaCl. How you would prepare this buffer? Provide a step by step description of how to make this buffer with details including rinsing glasses, how you would measure each item, volumes of water added to beakers and so on. Use the back of this page for your answer if necessary.

Explanation / Answer

Following steps must be undertaken to prepare this buffer:

Use the formula for each calculation:

Desired mass of substance = Molarity required * Molecular mass / 100,

where, formula weight are as below:

Urea: 60

Sodium chloride: 58.4

Glycine: 75

BME: 78

This will result in formation of a desired solution, volume 100 ml and pH 8.2.