something with the ammonium ion in it, or you ight could use liquid NH3, but that would be a pain in the ass.
My guess would be that you could prolly use ammonium chloride, but you might want other's opinions on it.
But you could just get household ammonia solution, and household venegar, and mix together to ph 7, then boil to dryness, and scrape up the ammonium acetate.
Do not go gentle into that good night. Rage, Rage, against the dying of the light. --Dylan Thomas