G418 left out overnight - (Oct/30/2014 )

I accidentally left out an aliquot of G418 overnight in the cell culture hood under regular light (don't ask, it was an accident).  Is the aliquot still good?  I guess I could get another 1 mL aliquot of stock from the core facility for $5, but I don't want to if I don't think it's necessary.

If in doubt, throw it out...