Probe synthesis buffer

62 μM each dATP, dTTP, dGTP

0.5 mg/ml bovine serum albumin (Fraction V, Sigma)

625 μM dithiothreitol

32 mM Tris-Cl (pH 7.5)

6.5 mM MgSO₄

Store the 3x buffer at -20°C in 100-μl aliquots. Use a fresh aliquot for each batch of radiolabeled probe. Discard the unused portion of each aliquot.