The document describes the Stratagene XL2-Blue ultracompetent cells, which are high-efficiency derivatives of XL1-Blue supercompetent cells. The kit includes 10 x 100 µl of cells, a pUC18 control plasmid, β-Mercaptoethanol, and materials for transformation testing. It specifies that the cells must be stored at -80°C on dry ice and guarantees an efficiency greater than 5 × 10⁹ cfu/µg of pUC18 DNA.
The cells guarantee an efficiency greater than 5 × 10⁹ cfu/µg of pUC18 DNA.
Optimal transformation efficiency is observed when cells are heat-pulsed at 42°C for 30 seconds.
It is important to use 14-ml BD Falcon polypropylene round-bottom tubes.