Use a strong alcohol. I use 190 proof grain alcohol that I buy in bulk from www.organicalcohol.com. It is expensive, so if you only want a small amount you could go in on a gallon with a few friends. Everclear is another option. You can find it in a store where they carry liquor, but you will have to ask for it. Rubbing alcohol is the next best alternative. Vodka is not really strong enough, and it’s iffy as far as killing off viruses is concerned. But if vodka was all I had, I’d use it.