dilution question - basic question (Sep/02/2007 )

What is an easy way to make up a 50uM solution of powder substance X which weighs 257 g/mol? I'd like to add this concentration to a 1L solution of water and still keep the concentration at 50uM after addition. How do I go about doing this?

it depends how acurate a solution you want to make.

But I guess an easy method is to go via serial dilution

First make a 100mM solution of substrate X.

The add the appropriate volume of 100mM solution to your 1L bottle and top that up to 1L. If my calculations are correct that would 0.5ml of 100mM.