How long is Isopropyl alcohol good for?

[tmfinley]

My question about reusing syringes brought me to this question. To disinfect the syringes I am soaking them in the alcohol for 5 minutes and then storing them in a ziplock bag. I have the alcohol in a tall shot glass covered with saran wrap. How long will the alcohol be good for? I didn't want to have to refill the glass with every new syringe. I think I've seen things in a doctors office stored in alcohol. I found a few sources on the web saying it has an expiration date of 3 years, but nothing for how long it is good after poured and being used. What do you think?

[grimm_mojo]

i would think it be good till it evaporates or it gets really dirty

[fishinsoap]

properly sealed it should last for as long as you want it to. Evaporation is your only enemy if you keep contaminates out.