Good day everyone.
Just a short question here, we are currently doing some chemotaxis assay.
Is there any chemicals or subtituents which can replace sodium azide as anaesthetic agent?
Thank you. 
without knowing why you don’t want to use azide, how about 0.1% tricaine and 0.01% tetramisole?
First is because we are not quite sure about the handling of sodium azide.
From the information acquired, the salt cannot be taken out with metal spatula as it is very hazardous.
Also we have limited amount of it. Maybe can enlighten us on the handling part?
Thank you for the recommendation. A side question, is it possible to use chloroform?
Again, thank you
true enough, most safety regulations say metal spatulas are a no no. But you can use plastic or ceramic spatulas instead (Sigma has these). Just watch out for the static electricity on the plastic…sometimes chemicals get sprayed around by it.
Apart from that, normal precautions…don’t suck your fingers, scratch your nose, breath it in, add it to acids, absorb it onto your skin, get blow back from a hood, add to water then spray the solution over your colleagues etc. etc.
Some sites even suggest only weighing out when the PI is present (from my experience of some new lab recruits, I would tend towards the opposite).
Chloroform will put them to sleep…period! It is a relatively blunt instrument as it is so volatile…the entire plate would go nite nite if you kept the lid on.
I never knew about the no metal spatula with azide!
I recommend you just scrounge around nearby labs if there are some to get azide, it’s quite commonly available. It works very well, you don’t need much, and there’s no telling how your assay would be compromised using another agent.
me neither D:, I always wondered what that dusty bag of plastic spatulas that nobody ever uses was for…
I first worked as an undergrad in a cell culture lab, where I was told not to use a spatula at all if I could help it, they were very paranoid about contaminants getting into the stocks. If you’re careful and patient you can usually tap it out of the bottle.
If you don’t want to order a plastic or wooden spatula, a bit of folded weighing paper can often be effective.
i always used a metal spatula and nothing happened until i used it to put a few crystals into a flame. nice air bag demo.
using very small amounts I guess you would likely never have a problem with a dry metal spatula.
In contact with water sodium azide converts to hydrazoic acid which is even more shock-sensitive (=will explode). Heating is a sure fire way of getting a bang.
That said, someone managed to total a fume hood with 80g of azide…as Verbal Kint would have said, ‘****ing chemists’.
I see I see. Thank you for the kind replies
To be on the safe side, I should prepare the sodium azide solution in fumehood right?
Sigma do a 1% solution I think, but then that’s about 150mM. That would spare you the anxiety of doing it yourself…but its more dilute than recommended and hence you need more (say 10µL against 1µL).
With care and enough protection (mask, eyeshield and gloves) you could safely weigh out the 65mg in an Eppendorf (at the bench) and dissolve the azide in 1mL of water (in the hood). Just need to work carefully and be aware of possible spills/contamination.
Of course, many are not so fastidious about this…but I guess you don’t want to be the one who poisons themself or someone else, right?
Steve