- 10-10-2004, 11:26 PM
Im looking to buy a re-usable vacuum filter. If you have one, please post where you got yours. I would like one that filters into pre-sealed vials, so I dont have to transer, but im not gonna be picky. All the websites ive been looking at have different kinds, but they have limited photos, and I dont know if its really what I need. Any info will help
- 10-12-2004, 12:33 AM
10-17-2004, 12:30 AM
01-21-2005, 08:58 AM
01-21-2005, 07:30 PM
02-11-2005, 06:51 PM
The vacuum pump will work fine with the vacuum filtration units, but the disposable filtration units are nothing but problems. There are at least 20 different units available from different manufacturers, but no one seems capable of manufacturing one which will work for us. I believe Millipore is the only manufacturer which has a PVDF vacuum filtration membrane, but they use a polystyrene base and housing which dissolves using the mildest of solvents. Everyone else either uses polystyrenes in their construction as well, or uses substandard (to us) filtration membranes. Nalgene is a lone example of a superior molded polypropylene housing, and blows it by using a substandard CA filter membrane.Originally Posted by Bleeding_Fina
02-11-2005, 11:53 PM
So what would you guys recommend to someone who's tired of the handcramps associated w/hand filtering 75 cc's of gear.
02-12-2005, 04:38 AM
Take a motrin and keep switching hands! I know it sux, especially with 0.22micron filters. Use a glass rig for the auto-pump. The plastic ones degrade and Teflon is expensive like a mofo.Originally Posted by Sticks
02-12-2005, 11:29 AM
02-13-2005, 07:34 AM
OK, your right bro. I meant, take an oxycodone cap, slam a few beers, and do some finger warm up exercises (Noooo, not that kind either!) Filtering sux! I just wait and do it all at once so I don't have to screw with it again for awhile. I should just get a pump and some side-arm flasks and make it fast and easyOriginally Posted by bow
02-14-2005, 07:41 PM
Whatman is definitely the cheapest way to go; and even though there are other ways, let's admit it -- most of us are too cheap to spend any extra on newer filtration methods... heck, we do it ourselves to save as much dough as possible in the first place. However, there are other options which do work, and they are as follows:
1) Millipore 40mm centrifuge vacuum units -- used in conjunction with whatman prefilters, these vacuum units are a delightful alternative to syringe filtration. It takes awhile, but your hands do not hurt like h***. They work great for 50-200ml
2) All-glass filtration setups, various -- I sell more all-glass setups than I do anything else. They work flawlessly, and the only drawback (if you consider it so) is they have to be cleaned and sterilized every filtration cycle. They sterilize with filter in place, in a sterilization pouch, after the unit is cleaned.
3) Millipore 73mm steritops -- although they only last 1-4 hours and use polystyrenes, as long as you keep your usage to within this parameter there have been no complaints on the nearly 200 I've gotten rid of. They are useful up to 1000ml with the .45um filter unit, but really are not a good idea to use, IMO; you have to use glass lower units, however, as the plastic lower units don't hold up.
4) Millipore hi-cap 10cm2 filters -- filter 3-4X faster than the whatmans, but the filtration media blows at 45psi. They work well once you figure out bursting pressure, though, but are fairly expensive for the luer-lock version. Here is the thread for the flow tests, and I will update that thread in a few days.
5) Stainless steel pressure units -- these units are the cadillac of flat membrane filtration (at least for what we can afford; there are some really nice dedicated filtration units of different sorts out there but...), and filter a full scale of magnitude faster than comparable glass units. $$$
New test samples will be sent to mods shortly to re-test filtration capabilities of the disposable units. They will let you know what works and what is crap.
Last edited by GIJoe; 02-14-2005 at 08:10 PM.
02-14-2005, 11:57 PM
Shiii.... I'm not a mod, but I'd test the **** out of it and let everyone know if was a good model or not. I'd like the glass and SS versions you spoke of w/ a Buchner type 1 piece or porous glass lower unit that could support a .22 PTFE or acid resistant carbonate membrate. What are your prices?Originally Posted by GIJoe
02-15-2005, 02:31 AM
02-16-2005, 10:14 AM
47mm reusable syringe filters
47mm reusable syringe filters have made themselves available to me, and while not cheap initially, they are reusable. If they're any good, I'll post a new thread with the info.
02-18-2005, 08:53 PM
Nonsterile vacuum filter that may work
I have located a vacuum filter made out of polypropylene with the appropriate filter media, perfect in every way... except that it only comes nonsterile. They are used for solvent filtration, and stated max. temp is 45C, but I think they can be sterilized. I have bought a few of them and will post if I am able to sterilize them without plastic distortion.