Equilibration Buffer

Reagent	Final concentration	Amount
Tris-HCl, pH 8.0 (1 M)	20 mM	10 mL
NaCl (5 M)	300 mM	30 mL
Urea	8 M	240 g
ddH2O	N/A	Bring up to 500 mL
Total	N/A	500 mL

Combine Tris, NaCl, and water to 300 mL. Add 50–100 g urea at a time until all urea dissolves. Make up to 500 mL. Filter sterilize. Store at 20°C–24°C for immediate use or 4°C for up to a month.