Ligation buffer

2x Fast Buffer

132 mM Tris (pH 7.6)

20 mM MgCl2

2 mM DTT

2 mM ATP

15% PEG (MW 6000) 5 minutes for sticky-end ligations 15 minutes for blunt-end ligations.

NEB 1X T4 DNA Ligase Reaction Buffer 

50 mM Tris-HCl
10 mM MgCl2
10 mM DTT
1 mM ATP
pH 7.5 @ 25°C