Bnizzle....urine can keep in the fridge for approx 5 days (give or take 1) or it will keep in the freezer for about 1 year. If you freeze it, then remove it from freezer to fridge a day before and let thaw slowly. Then about a hour before you need it set on counter and let it come to room temp. After that, nuke for 10 seconds like QF and secure in place (making sure initial temp is around 103). Hope this helps.

P.S. I've used the frozen method many times with NO problem with LAB tests.