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Conversion of primer unit - ug/ul to uM (Mar/08/2010 )

I need to convert 50ng/ul to 50uM for my random hexamer.

How do I do this? :)


Have you already resupended your primer?

Does the primer vial by chance say 50 ug/OD?


I don't have the original vial now so I do not know the molecular weight or the OD of the primer. What I know is only that it is 50ng/ul. And I have to use 50uM of the primer.. Help help.... :D


well 1st of all its not possible to convert grams to moles untill the molarity is not known as you dont have the original vile...

but lets give it a try as nanogram (ng) is thousand times smaller than microgram (ug) (same is for nanomoles and miromoles). So as the stock ur having says 50ng/ul, and in order to make it equivalent to 50um...u need to take abt 1000ul from the stock. i am not 100% sure if its right....

-Bilal Malik-

A random hexamer is a primer with 6 bases. The MW of 1 base is 330gr/mol therefore the MW of the random hexamer is 6x330= 1,980g/mol.

With that in mind, in each 1ul of your 50ng/ul stock you have 25pmoles, or in other words your stock is at 25uM.

Now, if your stock is 25uM you can not make it 50uM, but sure you can adjust the volume you need from this stock for your reaction.

-almost a doctor-