FAQ: How can I determine if my NEB 10-beta cells are competent?

The pUC19 control DNA included in the kit is provided in case the user would like to confirm the competency of the provided NEB 10-beta Competent E. coli cells. While this is not routinely required, the transformation efficiency can be independently confirmed by transforming 100 pg (2 μl of the 50 pg/μl stock) into 50 μl competent cells and following the normal transformation and plating protocols. The resulting transformation efficiency should be > 1 x 108 cfu/μg pUC19 DNA.