Freezing the worms

Hi all,

i read from Stiernagle’s “Maintenance of C. elegans” describing that :
The keys to a successful freeze are using animals at the correct stage of development, the addition of glycerol to the
freezing media, and a gradual cooling to -80°C. Freshly starved young larvae (L1-L2 stage) survive freezing best.
Well-fed animals, adults, eggs and dauers do not survive well. It is best to use several plates of worms that have just
exhausted the E. coli OP50 lawn and that contain lots of L1-L2 animals
. A 15% final volume of glycerol in the
freezing solution is used.

May i know if anyone has experience by doing this? → after bleaching, rock the worms in M9 overnight, then freeze the L1 arrested worms directly?

Hi Tyrael

I’ve never done it that way before, although I’m not sure why it doesn’t work. When I freeze down I just let a couple of plates starve for a day, wash them off in M9, add freezing buffer, aliquot and put in the -80. The majority of the worms tend to be mainly L1-2, and I’ve always had good results.

Best of luck,
Ben

We tried this once and observed very low survival rates. The recommended protocol works well.

-Harold