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The CQ line of ultrafiltration membranes from GE is being discontinued. At this time, these membranes do not have any direct replacements, although we still carry other GE membranes which may be suitable for your application.  We've listed the specifications of the CQ membrane line below to aid comparison with other flat sheet membranes:

*GFD = Gallons per square foot of membrane per day The following products are no longer being offered:

• YMCQSP3001
• YMCQSP1905
• YMCQSP425
• YMCQSP475

If you need assistance finding a suitable replacement product, please contact us.  You can also click here to browse the other ultrafiltration membranes that Sterlitech carries.  

Our friends at Foxx Life Sciences have a new video demonstrating the features and innovations incorporated into the design of the Autofil Bottle-top Filtration System. Check it out below:

You can also click here to browse Sterlitech's entire selection of Autofil systems and accessories.

Sterlitech is proud to announce that it is adding Synder Filtration’s polymeric membranes to its stable of products.  These additional products increase the selection of available molecular weight cut-offs and include membrane filters with surface charges. “We have seen a steady increase in customer demand for our membrane process testing equipment, and correspondingly, a wider demand for a greater variety of flat sheet membranes,” explains Sterlitech President Mark Spatz.  “The addition of Synder Filtration products illustrates our desire to support the wide-ranging needs of our customers and facilitate the development of new applications.” Synder’s flat sheet membranes characteristically yield stable flux, consistent rejection, and high mechanical strength and integrity. In addition to an optimal balance of flux and rejection, their ultrafiltration PES membranes offer one of the widest ranges of molecular weight cut-offs available, excellent resistance to pH, temperature, and fouling.

Over the years, we have received a number of questions about the optical clarity of our polycarbonate (PCTE) membrane filters.  Optically clear membranes are of importance when viewing plankton from the Antarctic under a microscope, manufacturing porous PDMS chambers, epifluorescent microscopy, and numerous other applications studies or even unmanned biology missions into space!   All of our polycarbonate membrane filters are made by the same process, track-etching, but the clarity of our filters varies based on both the use of the base film (amorphous or crystalline– we use both) as well as the pore size and density.  To shed some light on (or through) the matter of our filters' optical clarity we put together a handy infographic that you can check out at the bottom of this page. 

Amorphous polycarbonate has no defined molecular arrangement within the film, and as such tends to show greater clarity (in an otherwise untreated film) when compared to crystalline PCTE.  Crystalline

Sterlitech Corporation is now offering fully customizable membrane and process development systems which provide users with complete experimental control over the system’s flow parameters to simulate the dynamics of larger membrane systems.  Sterlitech first began building custom-made crossflow systems in 2011 and has since improved and expanded their capabilities to cover a wide range of applications in reverse osmosis, nanofiltration, ultrafiltration and microfiltration. These units can be individually tailored to meet the specific testing needs for off-the-shelf or custom membrane designs. Customizable factors include: membrane size, the number of cells in operation (up to 6), and whether the cells are run in sequence or in parallel.  Some of the new features built into the new testing units include a NEMA-standard waterproof touchscreen HMI panel and new back pressure regulators for better testing performance. This previously unattainable degree of flexibility is responsible for

Sterlitech's offices will be closed on Friday, July 4, in observance of Independence Day. We'll be back on Monday, July 7 to help you find the best solution to your laboratory filtration questions.

Defining a Pore Size and Sterile Filtering; 0.2 Micron vs. 0.22 Micron.  What’s the difference?

If you were to spend a little time perusing Sterlitech’s selection of membrane disc filters, one thing we’re very proud of might just jump out at you: we have a lot of pore sizes. So many that you might wonder if it’s a little excessive that we carry both 0.2 and 0.22 micron pore sizes. After all, both are used to sterilize fluid passed through them. Can the tiny difference of 0.02 microns really change a filter’s performance characteristics that much?

To answer that question, we must first take a look at one of the methods used to test a filter’s performance: the bubble point test1. Standard tests to verify a filter’s stated pore size usually entail a bubble point test. This test pushes air under pressure through a submerged membrane (either in water or alcohol) to the point where air bubbles first begin to come through the filter membrane2. The largest pore, or pores, in the membrane will