Hi,

I received a message from company that if I dissolve 1mg of streptavidin powder (Mw=13300 g/M) in 1ml I will get the "molar concentration" of 19.2 µmol/ml...

While if I calculate it myself it's obvious that this 1mg/ml would be a 75µM. (if the Mw is 13300 g/M or 13,3kDa according to MSDS).