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Using unopened restriction enzyme "expired" in 2010/11 - (Jun/14/2012 )

The many unused 'gems' we find in our lab from previous post-docs/students.

Would a restriction enzyme stored untouched at -20C be viable even after it's use-by-date?
Anyone who has used it before and seen that it stills cut perfectly?

-science noob-

I've used several REs that have been well past their use by dates, with no problem.

You could just give it a go and see?


It's common for labs in a research environment to use RE's that are years past their use-by-dates.
As long as the enzymes have been stored in consistent standard conditions they're almost always fine.
I'd suggest running a little test of them - if they work, they work. If in doubt throw them out.

If, however, you work in a regulated (that is, accredited) laboratory you'll have to look at if you can use these enzymes according to your system.
Speak to your supervisor.


I have used old enzymes many times. If they have been stored in proper conditions, you should not worry. I have used enzymes from 1998 and they worked perfectly well!