Hi, to prepare solutions you need to decide what volume of reagent you want to prepare (for example 1 ml, 100 ml, 1 L, ...). Then you should calculate the mass of your solid compound supposed to be dissolved in your solvent. For this:

1. Calculate "Moles" by this formula: Moles = Molarity (M) x Volume (L)

2. Calculate "Mass" using this formula: Mass (g) = Moles x Molar mass (g/mol)

Note: You can find molar mass on the reagent bottle or google it.

3. Dissolve the obtained Mass in the volume.

20 micromolar is very low concentration and needs to weigh very very small of powder. There is no scale to weigh these volumes. You should always prepare high concentration stock (e.g. 1 M, 100 mM, ...) and then dilute from your stock to reach desired final concentration. Here you can prepare 0.2 M stock. To prepare 1 ml (0.001 L) of 0.2 M celecoxib:

Moles = 0.2 x 0.001 = 0.0002

Molar mass of celecoxib is 381.373 g/mol

Mass = 0.0002 x 381.373 = 0.076 g

Dissolve 0.076 g celecoxib in 1 ml solvent (DMSO, ddH2O, ...). Now you have 0.2 M celecoxib stock.

To prepare final concentration of 20 uM celecoxib add 1 ul of 0.2 M stock to 10 ml of culture medium or any other solvent.

We biologists hate mathematics but this is just one reason why we needed it :)

Hi, to prepare solutions you need to decide what volume of reagent you want to prepare (for example 1 ml, 100 ml, 1 L, ...). Then you should calculate the mass of your solid compound supposed to be dissolved in your solvent. For this:

1. Calculate "Moles" by this formula: Moles = Molarity (M) x Volume (L)

2. Calculate "Mass" using this formula: Mass (g) = Moles x Molar mass (g/mol)

Note: You can find molar mass on the reagent bottle or google it.

3. Dissolve the obtained Mass in the volume.

20 micromolar is very low concentration and needs to weigh very very small of powder. There is no scale to weigh these volumes. You should always prepare high concentration stock (e.g. 1 M, 100 mM, ...) and then dilute from your stock to reach desired final concentration. Here you can prepare 0.2 M stock. To prepare 1 ml (0.001 L) of 0.2 M celecoxib:

Moles = 0.2 x 0.001 = 0.0002

Molar mass of celecoxib is 381.373 g/mol

Mass = 0.0002 x 381.373 = 0.076 g

Dissolve 0.076 g celecoxib in 1 ml solvent (DMSO, ddH2O, ...). Now you have 0.2 M celecoxib stock.

To prepare final concentration of 20 uM celecoxib add 1 ul of 0.2 M stock to 10 ml of culture medium or any other solvent.

We biologists hate mathematics but this is just one reason why we needed it :)

Perfect explanation. Just one comment - celecoxib is not very well soluble, even in DMSO. I would suggest to make 20 mM stock solution in DMSO and then to dilute it up to 20 uM.

Before making solution first find out the best sutiable solvent for the questioned drug. Rest of the calculations are already precisely explained by the above researcher.

Thank you dear Babak Nami for your explanation.

Dear Vilma Petrikaite and Shaharyar khan i also valued your suggestions.

Thank you.

How to prepare 20 micromolar solution of any liquid compound?