Sterilising Filters

They shouldn't require sterilization. Was the packaging open?

I suppose you could soak them in a mild metabisulphite solution, and then rinse them out. But then they wouldn't be very useful as filters any longer.

Or you could put them in the microwave for a few minutes. That should kill and micro-organisms without damaging the filters -- unless you leave them in too long.

They shouldn't need sterilizing as long as they're clean and stain-free, etc. I presume you'll be using them to filter an already fermented wine with a reasonable alcohol content - and the alcohol should kill off any minor germs.

Use vodka.

Internally or externally?

One shot for the filter, one for yourself!