I have drug RU-486 1G, I am supposed to make stock solution of drug in DMSO? How do I decide the stock concentration such that my DMSO is almost 0.1-0.2% in the final volume?
The final concetration of drug required is 40 microgram/ml
MW (RU-486)= 429.59, given RU-486 =1 gram, solubility of RU-486 in DMSO = 42.96mg/ml.
Make a 40mg/ml stock in DMSO & then dilute 1 in 1000 to give a final concentration of 40ug/ml with DMSO @ 0.1%.
Hello Yash Kulkarni
You make a stock solution of 100mM in 100% DMSO. Mol.wt.of RU-486 : 429.59
Calculation is as follows:
1M 429.59 g 1000ml
1M 0.42959g 1ml
100mM 0.042959g 1ml
100mM 42.959 mg 1ml
100mM 42.96mg 1ml
Weigh 42.96mg RU-486 and dissolve in 1ml (100%)DMSO (Stock solution).
Dilute the stock solution by 1:1000. It will give 42.96 ug/ml (i.e., 0.1mM). (Diluted stock).
(The DMSO concentration is diluted to 0.1% as the stock is diluted 1000 times. So it is suitable to be used in culture).
Use the formula C1V1= C2V2
Where,
C1= concentration of diluted stock (42.96ug/ml)
V1= Volume to be taken from diluted stock (say X)
C2= Concentration of working solution (40ug/ml)
V2= volume of the working solution (1ml)
42.96ug x X = 40ug x 1 ml
Therefore X = 40/42.96 =0.931ml
So, you will take 931ul of diluted stock and add 69ul of culture media to obtain a final concentration of 40ug/ml which will contain less than 0.1% DMSO.
Best.
- Badges
- Science method