Question

1) Prepare 1 L of 1X transfer buffer using the 10X stock

10X Transfer buffer (500 mL)

15.15 g Tris base + 72 g glycine

Fill to 500 mL with water

2) Calculate the molarity of Tris in the solution and the molarity of glycine in the 10X. The pH of the solution is 8.5. Then, calculate the concentrations of each component in the 1X solution.

Answer 1

1) we will take 50 ml of 10x buffer and dilute it to 500mL by adding 450mL of water to get buffer with 1X concentration.

2) Moles of Tris = Mass of Tris / Molecular weight = 15.15g / 121.14 g·mol⁻¹

Moles of Tris = 0.125 moles

Molarity of tris = Moles / Volume in litres = 0.125 / 0.5 L = 0.25 M

Moles of glycine = Mass of Tris / Molecular weight = 72g / 75 = 0.96 moles

Molarity of glycine = moles / volume in litres = 0.96 / 0.5 = 1.92 M

concentration in 1X solution

Molarity of Tris = 0.025 M

Molarity of glycine = 0.192M