Freezing home-brewed competent cells
Posted 24 January 2011 - 01:55 PM
I don't have a reliable source of dry ice, so I'd rather find a way to do it without. If they need to cool quickly, how about a metal heat-block, sitting in the -80 C? Else, slowly, how about a polystyrene enzyme box thing? You know the things I mean? They keep your microcentrifuge tubes all snug in those white plastic boxes.
Posted 24 January 2011 - 02:36 PM
Posted 25 January 2011 - 02:37 AM
I think it also has to do with how far you have to walk to the -80'C.
in my old lab, it was in the basement, and we were on the 5th floor - the lifts didn't always work and the stairs were very steep. so, if the -80'c was next to you - no problem.
Posted 25 January 2011 - 03:53 AM
Posted 26 January 2011 - 04:28 AM
Posted 26 January 2011 - 04:53 AM
Think of it this way -- if a short period on ice were going to effect competency much, then most of our transformations would fail because the cells invariably sit on ice for a while when you pull them out of the -80 to use them.
Posted 26 January 2011 - 05:35 AM