NGM agar and buffer

Hi, I’m an undergrad student and trying to culture C. elegans in the lab. The worms are being used to practice egg and worm isolation and washing techniques.
Right now I have my worms growing on plain agar with OP50.
I need to make up some NGM plates asap!! The problem is my lab does not have the ingredients to make up;
→ 1 M KPO4 buffer pH 6.0 (108.3 g KH2PO4, 35.6 g K2HPO4, H2O to 1 litre) and
→ 1M MgSO4
Does anyone know if 1. these ingredients are 100 % necessary (as I’m not doing anything specific with the worms) and 2. if there are any alternatives I could use that my lab might already stock?

I have cholesterol and peptone, does anyone know if I could simply add these ingredients to plain agar?

Thank you!


p.s. I have attached the protocol for NGM agar that I am following (trying to!).

it’s likely that you could grow your worms using plates made up with just agar + peptone + cholesterol.
probably better to have some kind of buffer included, e.g, you could make them 50 mM Tris pH 7.5.
worms are happier with phosphate and Mg added, but these are present in the peptone so they aren’t absolutely essential to add to the medium.

So, your undergrad lab has cholesterol and peptone (and agar I take it), but not MgSO4 or K2HPO4/KH2PO4?? Are you sure, the latter pair are almost ubiqitously used for buffer preparation.

Compared to some of the reagents you already have, getting the MgSO4 and the two K+ buffer reagents will not cost that much.

Who’s giving you the worms then? Maybe they should foot the bill…

Plus, if you want to do egg isolations, you will need to make up the appropriate solutions for that as well. Invest a little time now and not too much money so that you have the correct reagents for the experiments. Talk with your undergrad advisor and ask them? If this is an official project then they should be funding the chemicals!

If it’s unofficial, then you can still get everything you need on Ebay (you would just not be insured for working in the lab unsupervised/alone I guess :()


Awesome thank you!
I’ll whip up some plain agar with Tris buffer (we have the ingredients for that!).
It’s official but I only need the C. elegans to practice techniques with. My project involves H. polygyrus.
I need to be able to isolate and clean H. polygyrus eggs from mice faeces.

Eric! Don’t forget about your awesome 20 year old WBG article (!

Try out the different recipes Kew, might be worth a shot.