_{1. Pipette 200ul competent cells into each of 3 ice cold Eppendorf tubes. Label the tubes Control, 1 ng, and 10 ng (1 ng is 10} ^-3 _{ug, or 10} ^-9 _{milligrams). The unknown plasmid is at a concentration of 1 ng/ul. Add 1 ng of your unknown plasmid to one tube and 10 ng to the other. Place the tubes on ice for 30 min.}

_{2. Put the tubes at 42}^o_{C for exactly 90 seconds. Return the cells to ice for 1-2 minutes.}

_{3. Pipette the transformation mixtures onto labeled plates containing ampicillin and spread them around using a sterilized, bent glass rod spreader.} 

_{4. Place upside down in the 37}^o_{C incubator overnight.}

_{5. 16 – 20 hours later, count the number of colonies on the plate with well-isolated colonies. Put parafilm around the edge of a plate and put it in a refrigerator for later use. Check the control plate to see that no colonies grew on it.} 

_{Note: Competent Cell Preparation Procedure is given in the last post click older post to view it.}

_Reference

_{http://faculty.plattsburgh.edu/donald.slish/Transformation.html}

_{http://www.mnstate.edu/provost/TransformationProtocol.pdf}