Could competent cell be stored in liquid nitrogen? - (Aug/21/2007 )

I got some competent cells from a bio-company,and i sotre them in our liquid nitrogen container.does it have any bad influence on competent cell ?
thanks!

Nope. Had a labmate once that flashed freezed competent cells using fresh liquid nitrogen.

However liquid nitrogen is still a liquid and you can have stuff in said liquid. And since large dewars don't get cleaned out for years if not decades, there can be a buillt up. Finally competent cell (bacteria i asume) are still bacteria, which can be a source of contamination if stored with animal cell lines. (as unlikely as it maybe)

Perneseblue: Is "fresh liquid nitrogen" better than the ordinary stuff we've been using?

eh!? Nooo... Fresh nitrogen just comes from the big tank outside the building that gets topped of every 2 weeks by a liquid nitrogen tanker.

My old labmate just wouldn't use any liquid nitro that had previous contact with frozen cell stocks. He had his own hand held duwar and filled that up from the main tank. Rather then pour off nitrogen from one of the mobile temporary storage duwars.

i have tried this. i think competent cells could be stored in liquid nitrogen.
thanks for your answers.

Remember that you have to be careful about taking sealed tubes out of liquid nitrogen -- they tend to explode if any nitrogen has seeped into the tube.