The Nystatin (Sigma #N1638) that we use to make Enriched Peptone Agar
plates for C. elegans, is on back order until October.
I was wondering if other labs use nystatin powder or get nystatin
suspension from other companies? If so, could you please provide the cat.
number? Thanks.
Dominique
We also use Sigma N1638, but some labs use Sigma N3503. (for example Nature Protocols, 2, 1276-1287 (2007), I think.) You could leave it out of the recipe, also. The worms would be happier without it. Any mold or fungus will be happier without it too, though.
I’ve been using Sigma N6261-5MU, resuspended at 10,000 U/ ml in buffer- it’s the same thing as the pre-mixed version that’s back-ordered, and it’s much less expensive. Keep in mind that nystatin is not soluble in water, so you’ll get a cloudy solution that needs to be mixed right before using (just like the pre-mixed version).
Thanks for the info!
Dominique
At 10,000 U/ml, do you have any trouble filter sterilizing your Nystatin solutions? Though some of the suspended Nystatin gets through a 0.2um filter, enough residue is left behind to make it hard to estimate the final concentration.
Actually, I don’t filter sterilize it at all. I use sterile buffer to make the suspension, but since the nystatin is insoluble, it would probably get stuck going through any filter, anyway. I have never had any problems with contamination of my nystatin suspension.