Phenol (pH 4.7)

Phenol (Use RNA-grade phenol to minimize possible exposure to RNases.)

Tris-Cl, 50 mM (pH 4.7)

• 1. Add 10 mL of 50 mM Tris (pH 4.7) to 35 mL of liquefied phenol. Shake vigorously. Centrifuge at 2500g.

• 2. Remove the upper layer (Tris).

• 3. Repeat Steps 1 and 2.

• 4. Top off the phenol with 5 mL of 50 mM Tris (pH 4.7). Store in the dark at 4°C. Cover with aluminum foil if an opaque container is not available.