Cis Recording Solution

• 1. Take the amount of HEPES used to make 250 mL of trans recording solution and multiply by 8. Weigh out exactly that amount of dry HEPES powder.

• 2. Weigh out 30 g of highest purity Tris base.

• 3. Mix the Tris with the HEPES powder.

• 4. Add water to make a total volume of 2 L, and stir.

• 5. Measure the pH. Keep adding dry Tris, with stirring, until the pH reaches 7.35.

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