They explain all of that on the Outlawmuscle.com forums.
But to answer your question acetic acid will keep it active for 2-3 weeks.
Makes it burn like a bitch though when injecting.
Make sure you get some bacteriostatic water too, 1st inject the amount of igf into the syringe and then finish topping off the syringe with the b.water.
The water will then go in first to your muscle and dilute the acid which will minimize the burn.