how to calculate units - (Jun/14/2011 )

I have IL 2 in a bottle of 5ug. I need to dilute it in 100mM acetic acid to a final concentration of not less than 100 ug/ml. The activity of it is 5*10^6 U/mg.
Now I need 2000 U of il-2 for my experiment. So, how much volume of acetic acid I should dilute it in to get a stock of say 500U per ul?

you need to dilute to attain a conc of 0.1 microgram per microlitre, which contains 500 U (Assuming that there is 5000000 U per mg). so adding 50 microlitres of the solvent in 5 microgram IL2 would give you the desired conc. that contains 500 U per micro litre...from that you got to add 4 micro litres to get 2000 U...hope you got it!!!!!


Good luck...