how to dilute 100mM dNTP to 1.25mM? what is the calculation to make pcr reaction...

[paramita]

...work solution? I have stock of 100mM dNTP. I need to make 1.25mM for 25ul pcr reaction.I am confused about the calculation.If anybody help me please...

[protolder]

hola, 100/1.25=80 so you have to dilute your solution 80 times to have 1.25mM. But if this concentration is the final in reaction mixture, 25/80=0.3125ul 0r 3.12 ul of an intermediate solution 10mM (10ul of 100mM +90 H2O). Buena suerte

[Aurora Borealis]

The best and the most used formula I ever learned at school is this one:
c1*v1=c2*v2 where:
c1= the concentration of the solution you want to dilute
v2= the volume you should use of the solution
c2= the concentration you want in the final solution
v2= The volume you want of the final solution

So lets say you want to make 500 ul of a 12,5 mM solution the formula is:
c1*v1=c2*v2
100 mM * v1 = 12,5 mM * 500 ul
v1 = 62,5 ul
That means you have to use 62,5 ul of your 100 mM solution and dilute it in 437,5 ul of whatever you want to dilute it in to get a final volume of 500 ul. Then you have a 12,5 mM solution of your primers, and you can then use 2,5 ul of this solution in your 25 ul to get a final concentration in the reaction of 1,25 mM.

[m37786]

Very good answer
mahmoud manama