5X Long PCR Buffer

Contributed by Ian Chin-Sang, Queens University, ON, Canada

5X Long PCR Buffer (store in 1ml aliquots in -20C).

This buffer seems to work well with Worm Genomic DNA using Taq/Pfu (3:1) mixture.


425 mM KOAc 125 mM Tricine pH 8.7 (adjust pH of Tricine stock solution with KOH) 40% glycerol 5% DMSO 1.2 mM Mg(OAc)2


  • Combine ingredients in a suitable container. For 10ml 5X long PCR buffer use:
  • 4.25 ml 1M KOAc
  • 1.25 ml 1M Tricine, pH8.7 @ 25 degrees C (with KOH)
  • 4.00 ml glycerol
  • 0.50 ml DMSO
  • 120 ul 500 mM Mg(OAc)2
  • Store in 1ml aliquots at -20’C until required.

This method is based, with permission, on an original protocol available here.