calculating the cell density

Sulakshana Mukherjee mukherji at
Sat Oct 6 07:30:54 EST 2001

Dear all,
I am following a protocol for making competent cells. In this protocol I
am unable to understand the following step:
 " Determine the OD at 550 by diluting a small portion (e.g.,1%) of the
cell suspension 300x. Then adjust the volume of the concentrated cell
slurry with cold EWB(10% glycerol in ultrapure water) to produce a final
OD at 550 of 200-250 units/ml." 

with best regards,


More information about the Methods mailing list