how to make drug dilutions????

[hershee]

hi
can any one tell me how to make drug dilutions????
i have 5mg/ml cisplatin, and have to make 10nmolar/5ml, 20nmolar /5ml and 40nmolar/ 5ml dilutions
plz help me

many thanks

[danfive]

Originally Posted by hershee

hi
can any one tell me how to make drug dilutions????
i have 5mg/ml cisplatin, and have to make 10nmolar/5ml, 20nmolar /5ml and 40nmolar/ 5ml dilutions
plz help me

many thanks

1st step.
MW of cisplatin 300.05g/mol
You have 5mg = 0.005g in 1 mL
so 0.005g x 1mol/300.05g / 0.001L = 0.016 mol/L = 0.016 M

Now you have to clear up what you mean by 10nmolar/5mL.
Do you want the volume of the stock 0.016 M cisplatin to be put into a 5mL saline solution that gives you final 10nmolar concentration? or do you want 10nmole cisplatin diluted in 5ml saline (no regard to the final concentration)?

[danfive]

There are several molecular weights for cisplatin out there so please find the one that applies to you.

Anyway here is a conversion for you;

0.016M = 16mM = 16,000nM

You can figure out the dilution factor from there, for example:
DF = 10nM/16,000nM = 1/1,600 or dilution of 1,600
that means that 1microliter of cisplatin (stock 0.016M) into 1.6mL total volume = 10nM final solution.

If you want 5mL of the stuff
m1v1 = m2v2
v1 = (10nM x 5mL) / 16,000nM [mL is OK because nM/nM cancels out)
v1 (volume of stock cisplatin 0.016M) = 0.0031mL = 3.1 microliters
so 3.1microliters of the stock diluted into 5mL total volume gives you 10nM solution

[hershee]

many many thanks danfive,

your reply is absolutly valuable..

actually i wanted my stock of 0.016M to be diluted in 10nano molar concentration in final volume of 5ml.....another solution from stock is 20 nano molar in 5ml final vol.
then i will have 2-3 nano molar conc in 5ml..

is it easy?

many thanks

[danfive]

Originally Posted by hershee

many many thanks danfive,

your reply is absolutly valuable..

actually i wanted my stock of 0.016M to be diluted in 10nano molar concentration in final volume of 5ml.....another solution from stock is 20 nano molar in 5ml final vol.
then i will have 2-3 nano molar conc in 5ml..

is it easy?

many thanks

OK.
#1--you want 5ml of 10nM solution
setup as: 16,000nM x V1 = 10nM x 5mL
solve for V1 = (10nM x 5mL)/16,000nM = 0.003125mL= 3.125uL
Means you should mix 3.125 microliters of 0.016M cisplatin into 5mL saline

#2--you want 5ml of 20nM solution
setup as: 16,000nM x V1 = 20nM x 5mL
solve for V1 = (20nM x 5mL)/16,000nM = 0.00625mL= 6.25uL
Means you should mix 6.25 microliters of 0.016M cisplatin into 5mL saline

Note: I didn't bother tracking the significant figures.

[hershee]

danfive you make it very easy
thanks alot