Making 0.5mM stock solution of BME - (May/29/2007 )

This may be a simple question/answer, but I'm lost trying to figure it out. I need a 0.5 mM stock solution of beta-mercaptoethanol. I ordered BME from Fisher (BP176-100) and I got 89.74ml (100g) of BME (FW 78.13).

I've done the math every which way. Should I be starting with an assumption of the concentration of this solution. Do I use it straight? I figure I needed to dilute it to the 0.5mM. Do I need to dilute it in water?

HELP!

Make that a 50mM stock solution. Not 0.5mM!!!

2-mercaptoethanol is supplied as a 14.3 M stock with a density of 1.1168 g/mL.

Thanks so much!