Convert 400ng/ul to nM

I have DNA at a concentration of 400ng/ul and I want to convert this into nM. The molecular mass is 110,500. How do I go about doing this?

[JohnS]

Originally Posted by Unregistered

I have DNA at a concentration of 400ng/ul and I want to convert this into nM. The molecular mass is 110,500. How do I go about doing this?

Since Molar denotes moles per liter, lets look at a liter.
400 ng/µL is 400 mg/L. If the molar mass is 110500 g/mol, then the 400 mg is 3.62 µmol, so you have 3.62 µmol/L or 3.62 µM. This may be expressed as 3620 nM if you wish.

I don't inderstand how that came out the 3.62 can you help me?

[JohnS]

Originally Posted by Unregistered

I don't inderstand how that came out the 3.62 can you help me?

Divide concentration by molar mass