Per the link below...
Step 1
Treat storage mold by gently holding the daffodil bulb in your hand and wiping the surface clean. The mold should rub right off. You can identify simple storage mold by the fact that it will be dry and fuzzy rather than slimy. It will have a bluish hue. This mold forms because of humidity and inadequate circulation.
Step 2
Dip the cleaned bulbs in the 10% bleach solution for ten seconds to prevent further mold growth. Allow them to dry on a well-ventilated rack before planting.

I think that should do it just fine.

Sue

Here is a link that might be useful: Mold on bulbs