Syringe Filters PES Membrane, Sterile, 33mm Diameter, 0.22um Pore Size, Hydrophilic Filtration, Individually Packed, Pack of 50

I am pleased to share my positive experience with this filter. After trying several options over the past year that unfortunately did not meet my needs, I finally found one that performs exceptionally well for my lab work. This discovery has made a significant difference in my research, and I would highly recommend it to fellow lab professionals seeking reliable solutions.

Below after my product note here I have posted some important & factual research info about using these filters for home injectable poppy preperations. (Saving you from an abscess).As for these filters, these have the pre-filter as advertised which every single other brands PES filter I've used that state they have the pre-filter, don't!! See the pics, look at the thickness difference which is needed to accommodate the pre-filter.I also have started using the wider (33mm diameter) filters since I am making enough for several days over single use and storing in sterile tan inj vials by K-tek also found on Amazon. For single use preps the cheaper 25mm diameter filters are fine, just make sure to ALWAYS ONLY use PES and 0.22um filter pore size. Info on all that below.----- These filters are excellent for filtering home inj mixtures and solutions via a syringe attachment. I NEVER prepare a solution without these anymore, & have never had an issue since. A little money now saves misery later.- Studies have shown (can search online) that using filters filter out 100% of endospore forming bacteria that are common (in the inj poppy material) and can and do cause infections and abscess. These 0.22μm filters are the size that should be used. The Endospore bacteria are found to be no smaller than 0.8μm so these filter them 100%. Also the PES is found to not filter any of the "active compound" itself. The loss that can occur is from a drop or two that may remain in the filter unit.NEVER force air through to produce those remaining drops, it can compromise the filter integrity (these filters are meant for fluid, not gas (air)). A burst of a few foamy drops after forcing air through can mean the filter has been torn/dislodged and residual particulate and filtrate have been forced through or around the filter (the stuff you're trying to filter out & should be refiltered through a new filter). Instead of pushing air at the end pass a small amount of water slowly through after to get those last couple drops out.- Less fluid remains behind with the smaller 15mm or 13mm diameter filters than with the 25mm (that's the diameter size of the entire unit, not the micro-pore size of the filter material inside which should ALWAYS be 0.22μm)I caution against ever using 15mm or 13mm diameter filters as they will clog very quickly and they have far less surface area to filter those abscess causing bacteria. (the 25mm filters are rated for 10ml to 100ml total fluid filtered. Whereas the 13mm are rated only for 0ml to 10ml. Definitely a better value with the 25mm diameter filters). I don't myself reuse or suggest reusing a filter though as long as there isn't much resistance on repeated uses. Regardless of how much fluid you have passed through a filter, once you feel resistance don't force!! It's time to use a new one.--- A last note, NEVER use PTFE filters for your inj poppy fluid preparations in syringe. PTFE are hydrophobic (hate fluid) and best used for gas exchange filtration. And the Nylon can tend to bind protein and amino acids which can result in filtering a bit of your "active compound".Use the PES filters only for home inj preperations.(poppy).

They work very well for filtering liquids for injection. Essential to maintain the purity of therapeutic compounds.