Southern blot neutralisation solution recipe

Base: 1 L · pH 7.5 (adjust with HCl) · Updated 2026-10-01

Brings the denatured gel back to neutral pH before transfer: 1.5 M NaCl, 0.5 M Tris-HCl pH 7.5.

🧮 Volume calculator
ComponentAmount Final concentration (1X)
NaCl87.66 g1.5 M
Tris base60.57 g0.5 M
Concentrated HClas neededto pH 7.5
Water (distilled)to final volume

Steps

  1. Dissolve in about 80% of the final volume of water.
  2. Adjust to pH 7.5 with HCl.
  3. Bring to the final volume with water.
  4. Soak the gel 2 × 15 min, then transfer with 20X SSC.

FAQ

Is EDTA sometimes added?

Yes — a 1 mM EDTA variant is common.

This is a widely used standard composition. Amounts depend on the hydrate form and purity of your reagents — check the formula weight (FW) on the bottle and follow your institution's safety rules and the manufacturers' instructions.