[Notgoodatcalculations]

Hi,
I am having trouble with this calculation.
I need to perform a strevptavidin conjugation to biotinylated-completment.  The biotinylated complement is 3"BiotinXXXXXXX at 200uL of 500uM Stock.

I know streptavidin consists of 4 subunits with a MW of 13000, each containing a single biotin binding site.  The Streptavidin comes in at 10mg/mL. I have 100uL of it.
The molar ratio of 1 mole of streptavidin +4 moles of biotinylated molecule (assuming I have 1 biotin/mole of molecule).

What is the calculation I should use to get the right ratio?