# Calculation - (Jun/02/2013 )

Hi,

I have stock solution of

1)DTT (1mM)

2) NAD+ (2mM)

3) PGM (1.2U/mL)

4) G6PDH (2U/mL)

I will need a final volume of 200ul with the following:

1) DTT(0.5mM)

2) NAD+ (1mM)

3) PGM (0.6U/mL)

4) G6PDH (1U/mL)

Can anyone give hints/formula on how to do the calculation? Many thanks!

Hi Ic3_88,

You can use M1V1 = M2V2 to calculate the amount of volume required to make your solution with desired concentration and volume. For example:

M is moles per litre or the concentration; V is the volume of solution in litre. So, M1 is the concentration of your stock solution; V1 is the volume of your stock solution; M2 is the concentration of solution you want; V2 is the final volume you need.

In order to make 200 uL of 0.5mM DTT from 1mM DDT, you will need:

M1V1 = M2V2

(1mM)(x) = (0.5mM)(200 uL)

x = 100 uL

It means you'll need 100 uL of 1mM DDT in 100 uL of water/ solvent you used to dissolve the DDT powder. So 100 uL of stock solution and 100 uL of water/ solvent will make a total of 200 uL.

Likewise, the rest of the solutions can be calculated using the same formula. Hope this helps...=)

Catherine

are you making 4 solutions or one solution with the 4 components.

if 4 solutions then just dilute each one with an equal volume of diluent.

if one solution with 4 components then you can't do it with the stocks that you have.

Hi,

I need to make one solution with the 4 components.

Ic3_88 on Mon Jun 3 14:15:56 2013 said:

Hi,

I need to make one solution with the 4 components.

Is your stock solution a mix of the 4 components at the concentrations stated? In which case you just need to do a 2-fold dilution for your final concentrations.

Or do you have 4 stock solutions (one for each component)? In which case, as Mdfenko said, what you want to do is impossible.