Question about unit - (Jul/17/2006 )

Hi,
What does the U stand for?
For example, penicillin, 100U/mL

U stands for units.

Penicillin G - 500 000 units is equivalent to 312 mg.

Thanks,
Where do you find the info about conversions like this

Ah but you have to be very careful. Not all units are standardised. Many companies define their units differently. For example the DNase I enzyme available from Sigme and Promega are supplied as, say, 50 U/µL but the U is measured in a different way for each. The only real way to be 100% sure is to check the product notes that come with the item. If you haven't got those then some companies have them on their websites and others will e-mails them to you if you call or e-mail them with an enquiry