Just go with a whatman zap cap CR and use a 70mm prefilter paper for anything. Works fine, very well actually. Supposedly they were discontinued but they are still widely available, I'm assuming stock already made, but if you actually get a medical laboratory vacuum pump you can try a fast cap which I believe filters at 15 liters per hour and you can get those as a .1.
.45 will only block passing bacteria, there is no known bacteria smaller than ,45 microns.
.22 will stop viruses as well, all know viruses and bacteria are larger than .22 microns.
.1, this will stop everything down to microbes. Which you can get this size as a fast cap, a medical laboratory pump doesn't have to cost a million dollars, they are oil less and will have and in and out port, most remind me of old computer towers, it has an on and off switch, they are quiet, and you can adjust the vacuum pressure. The good thing about a zap cap is you really can get it to pull 27hg with no problem, and I. Any remember the max pressure rating on a fastcap as they are new to me. But also pay close attention to the max temperature rating for any brand of filter you decide to choose. You can possibly melt parts of the filter paper if just a little to hot and most times wouldn't see it, but it will be painful and I imagine not good for you. And it can burn through your filter and it will just all run out.