Preparing ethidium bromide stock solution. - (Jan/05/2010 )

Hello, I need help preparing ethidium bromide stock solution. I have the powder but the concentration is supposed to be 10 ug/ml and I can't measure out that small of a volume plus the powder has a clumpy consistency which makes it hard to work with in the first place. Can someone tell me how to make this working solution?

Thank you

The usual stock solution concentration of EtBr is 10 mg/ml, or 1000x higher. Are you sure you need the lower concentration?
I would make this by first making a 10 mg/ml stock and diluting 1000x (assuming that this is what you really need).

By default,
EtBr is actually 10mg per ml
we used to convert it to .5 microgram per ml