DNA sequencing: Difference between revisions

(Added information on diluting primers)
I order primers from IDT, and it often says something like "Yield 26.3" - In that case I would add 263 microliters of water to make the 100 micromolar stock solutions. Then in a smaller tube I would add 180 or 190 microliters of water and 10 or 20 microliters of the primer stock solution to make a working primer solution. I add 1 microliter of each primer to a PCR reaction.
 
I store the 10 micromolar stock solutions in the fridge, they are good for a few months at least, and the 100 micromolar stock solution in the freezer - the colder the better. Primers are most stable when dry so it's best to wait until you need to use them to add water - however they are pretty stable in aqueous solution too, as long as the water is very pure (PCR grade is best).