DIY Lab-grade filters?

[Gravitysrainbow]

One might find one's self confused
with lab-grade filters out of reach...
But what to improvise to use
in place? Those who know, please teach

[/shakespeare] Is there anything out there, say, in a hardware store or Walmart
that would function almost as well as a 1 micron filter? I'm talking far better than coffee filters/cotton

[Larkin]

ive been thinking about this a lot lately. I think using n95 dustmasks would be a good bet. I think they block down to 50 microns, still better than a qtip i would think

[Flowergirl]

Rip apart aquarium water filters? What about fridge filters? The latter are expensive, the one I just bought was $40. Do you just like to fuck with stuff and you just want to see if you can create something? Otherwise, it seems smarter to buy them knowing the VERY little I know. That way, you know what you have and that it works like it is supposed to.

[Prasch]

I have no idea but loved the little rhyme you posted!

[port rhombus]

Is it really "impossible" for you to order some 0.22 micron luer lock filters online?

Not trying to be sarcastic or a dick... serious question.

I'm all for ingenuity, but this seems like it's not worth the risk. At least not if safe/accurate filtering is what you seek.

[Gravitysrainbow]

Port Rhombus, that's definitely possible but I'm looking to filter the results of an intermediate stage, not load up the finished product for use.

And I thought I'd ask because there's always the chance that someone'll reply "oh, x product filters just about as finely as commercial grade filters plus it's half the price and widely available.."

[Woody Bear]

What type of filter really depends on what you're using it for, and what you're attaching it to. If you're filtering through a syringe, and want a finer filter than a cotton, then wheel filters are the best thing.

If you're filtering through a Buchner funnel, then lab paper filters are the best thing, they are not so expensive really, especially if you look on auction sites every couple of days and look out for the good deals that occasionally come up.

If you have a Buchner funnel, and want better filtration that paper filters provide, you can add a layer of diatomaceous earth. That will provide much better filtration ability, and won't block up nearly as quickly, although the filter speed does slow down so much, that DE is useless unless you are doing vacuum (or pressure) filtration. Gravity filtration is almost impossible though a DE filter-cake.

Also I have used cut out circles of coffee filter paper with DE before, the coffee filter worked almost as well as normal lab paper filters. The only difference is that the coffee filter allowed more DE to fall through at the start when the DE + solvent mixture is poured onto the filter. But I don't use coffee filter's anymore, because lab filters are so cheap and easily available on auction sites, and when there were really good deals, I stocked up.

Lab paper filters don't work so well for cold water extractions on codeine + paracetamol pills, they block up almost immediately. This is because of the stuff they add to the pills, combined with the fact that the smaller the pore size, the easier it is to block up the filter.

I have used a piece of silk to filter out codeine + paracetamol pills, and this worked reasonably well, as the silk has such large pores that the solution passes through easily, but even the silk blocked up, so it needed moving about and agitating quite a bit to work all the liquid through.

[jimmyfingers]

I assume you mean wheel filters.

I am not aware of anything, but I am sure their are thing that would work. However, they aren't going to be 'lab grade' which is an important fact for IV use.

Wheel filters run 4-5 dollars a piece. IMO, expensive, but certainly money well spent. You can do some research and find out how to make a 'solution' Ex. Preparing 30 Oxycodone pills at once and storing the solution in a sterile vial with some bac water instead of fixing one pill at a time.