Hey /p/ee fags

I've always taken good care of my equipment, but sometimes I get in the situation that I need to clean my front element with more than just a microfiber cloth because of some sort of dried in liquid (inb4 semen) I don't wanna smudge. I often just breathe on it and try to whipe it off. But is there better alternatives? I've seen you can buy some expensive liquid for the purpose, but can't I just use isopropanol (rubbing alchohol) or alchohol in general? Do I risk destroying some of the coatings? What are your experiences?

Halp