Sterile Filtering: Do I Need a Sterile Filter?

I realize it sounds redundant.

The cost varies greatly between unspecified syringe filters and those labeled ‘sterile’.

From a practical standpoint, how likely is it that the [0.2um] filter itself will contaminate the solution?

A sterile filter is $4.25.

No one here can tell you how likely it is that a syringe filter would contaminate the solution.

Why is a couple dollars even an issue?

My intention was to create a discussion/solicit evidence that would help people make informed decisions. At least know the risk before you take it.

Do you think they process the sterile ones differently? I think it’s worth considering the (potential) differences.

It raises the question of ‘why not’ for the filters sold that are not sterilized. If they have the facilities, why not limit your liability by sterilizing everything? I don’t imagine they make the non-sterile ones in an open-air factory without any running water. You’re going to tell me the cost of running the autoclave is prohibitive?

I also question difficult-to-back statements like sterility when filters come in thin polyethylene bags that are easily punctured.

Pan, I’m going to (mostly) dodge the financial aspect because I’m ambivalent. That’s not my focus. I agree that it’s not a lot of money, and you can prepare a larger volume, knowing it will be sterile/store well. On the other hand, it seems many use the unspecified filters without issue (and many drug users use [not-brand-new] cotton, generally without issue). Then my question is why would you waste money?