Sterlitech Blog

Your source for new information on filtration equipment applications and processes.

  1. Discontinued Cytoclear Glass Slides

    Discontinued Cytoclear Glass Slides

    Cytoclear Glass Slides have been discontinued by the manufacturer due to lack of commercial interest, and are no longer available for purchase. These slides were previously used to enhance microscopic visualization with PCTE and PETE membrane filters, using a special light diffusing coating that significantly reduces the appearance of the pore edges by minimizing pore edge shadows.

    If you are looking for alternative solutions to enable improved microscopic work, Sterlitech recommends wetting the membrane with a liquid that has the correct refractive index and illuminating the membrane with polarized light. For example, the PCTE membrane is birefringent and has two refractive indices, 1.584 and 1.625. To minimize the appearance of pore edges, this membrane should be wetted with a fluid that has a refractive index of 1.584 and illuminated with properly-oriented polarized light.

    Please contact us if you have any questions. To view our other membrane accessories, please visit

  2. Introducing: Hydrophobic Polyester Track-Etch (PETE) Membrane Vent Filters

    Introducing: Hydrophobic Polyester Track-Etch (PETE) Membrane Vent Filters

    Sterlitech has a new option to consider for your vent filter applications: hydrophobic polyester track-etch (PETE) membrane vent filters. The PETE membrane has been modified using a proprietary process to be rendered permanently hydrophobic. These filters may be considered for vent applications where PTFE or polyolefin membrane filters have been traditionally used. The PETE membrane filters have superior dimensional stability compared to unsupported PTFE membrane filters and have better thermal resistance than polyolefin membrane filters. Additionally, the PETE membrane filters typically have greater water entry pressures than similar pore size rated PTFE and polyolefin membrane filters while maintaining reasonable air flow rates. Finally, the inherently uniform pore structure resulting from the track-etch manufacturing process ensures that PETE membrane filters have exceptional lot to lot consistency.

    The hydrophobic PETE membrane vent filters are suitable for a wide variety of applications including vents on electrical enclosures, allowing for passage of air and other gases (such as water vapor) while preventing passage of liquid water, particles and microorganisms. The PETE membrane vent filters are also oleophobic to AATCC118 grade 5 and, consequently, can repel oils and solvents with surface tension >25dynes/cm.

    Available in a variety of pore size ratings: 0.2, 0.4, 1.0, and 1.2µm, and backed with a nonwoven polyester support layer, hydrophobic PETE membrane vent filters are easy to handle and can be supplied in custom shapes with pressure activated adhesive. Interested to learn more about this product and its use in your application? Contact Us to connect with an applications specialist.

  3. Sterlitech to Provide Larger Scale Membrane Skids for Research and Industry Customers

    Sterlitech to Provide Larger Scale Membrane Skids for Research and Industry Customers

    These pilot skid systems are specifically designed for pilot testing of spiral wound membrane filters or small scale filtration processes. They offer more than 200 times the filtration surface available in standard bench-top filtration systems, allowing users to increase throughput and obtain results that translate for scale-up. Digital skids enable hands-free monitoring of process parameters and eliminate the need to manually record data.

    Built in benefits include:
    · Pre-assembled and plug-in ready
    · Digital or analog options
    · Customizable for chemical compatibility and application requirements

    Pilot Skid systems are developed for the next level of testing, once investigators have established the proof of concept their bench-top filtration systems. Testing with the Pilot Skid allows the investigators to use full size spiral wound membranes for evaluating new processes or products and gather operational parameters and tests results that are representative of those expected in the full size membrane filtration systems.

    Pilot Skids can be used in various applications, from new process and product development to quality assurance and materials research. They offer the opportunity to increase throughput in batch processing of water and wastewater, chemicals, pharmaceuticals, and other solutions. Mounted skid systems increase productivity and establish consistency in experimental control. Whether it is reverse osmosis, nanofiltration, ultrafiltration, or microfiltration applications, the Pilot Skid is a ready-to-use system for expanding a bench-top process.

    Technical support at every step of purchasing and implementing ensures users receive optimized design and an easy introduction of their new pilot system. Sterlitech also provides an operational training webinar within one week of delivery; each webinar is interactive and tailored to the skid design and the needs and skill level of its users. Our goal is to enable customers to seamlessly move their processes to pilot scale and promote continued innovation.

  4. No-Boo!-to Test Strips

    No-Boo!-to Test Strips

    Nobuto Blood Filter Strips are the bloodiest product in Sterlitech’s catalog; get some in time for Halloween sample testing! Made from high-purity cellulose fibers, these strips are structured for uniform sampling. Each strip holds approximately 0.1 mL of blood or 0.04 mL of serum.

    Once blood is applied and the strip has dried, researchers can analyze, store, or mail the samples without refrigeration. Studies have shown that these collection devices are easy to use and enable delayed analysis of samples collected in the field. The strips are a valuable resource for the diagnosis and surveillance of avian influenza viruses, Newcastle disease virus (NDV), and West Nile virus (WNV) in wild birds.

    Sterlitech offers Nobuto blood filter strips in packs of 100 with plastic drying racks that hold up to 40 strips at one time. In addition to common bird diseases, these strips can be used to test wild animals for a whole host of scary zoonotic pathogens including toxoplasmosis, hantaviruses, measles, plague, and tularemia. The strips can also support environmental studies by enabling researchers to monitor wild animal populations for heavy metals and toxins.

  5. King Cannabis Expo Recap

    King Cannabis Expo Recap

    Spokane county is home to the largest concentration of cannabis farms in Washington State, so we were excited to visit the source and attend the King Cannabis Conference & Expo in Spokane, WA. Representatives from Sterlitech connected with producers and processors from across the state to gain insight into current and emerging trends in the industry.

    At the expo, Sterlitech displayed its newest contributions to the cannabis processing industry:

    Fluxx Spigots: Achieve gurgle-free nutrient dispensing with efficient flow rates.

    150 mm Glass Assembly Extraction Kit: Perform high-volume cold filtration and speed up winterization with our largest extraction system.

    Absorbent Solvent Wipes: Keep work areas safe and tidy, now spill clean-up is a breeze.

    As the harvest season winds down, focus shifts to preparing harvested crops for sale or further processing. Post-harvest processing and extraction is a way for producers to add substantial value and create a diverse product market for consumers. Processing also presents an opportunity to utilize the leaves and stems of the plant, which are otherwise discarded. Due to its benefit to producers and consumers alike, sales of cannabis concentrates have been steadily increasing over the past few years and show no signs of slowing down.

    Interested in enhancing your cannabis processing activities? Contact Us to speak with an applications specialist.

  6. Why evaluate hydraulic fluid compatibility?

    Why evaluate hydraulic fluid compatibility?

    When introducing a new control fluid to hydraulic systems, it is important to ensure that the new liquid or mixture is of equal or superior quality to the previous fluid. If the new mixture is incompatible, precipitate may form and result in an overall inferior fluid. This can speed up clogging or damage the system.

    When a manufacturer of construction machinery releases a new line of bulldozers or backhoes, they may consider using a lower cost alternative fluid mixture. If the machines take a different fluid than previous versions, it may be beneficial to switch over to a single fluid for the entire fleet. The compatibility of the new fluid with the old can be assessed for quality to decide if the change is warranted.

    Similarly, an automotive die-casting company may want to convert from a water glycol hydraulic fluid to a polyol-ester fluid for higher performance and lower environmental impact on their cutting machinery. Examining the new fluid’s compatibility can yield valuable information during this type of transition as well.

    The ASTM D7752-11 Standard Practice for Evaluating Compatibility of Mixtures of Hydraulic Fluids outlines a filtration process for conducting an ISO 13357 procedure. This procedure is a dependable, standardized way to evaluate fluids and mixtures in a hydraulic system to ensure new mixtures are stable with each other.

    Ultimately, validating fluid compatibility does not necessarily promise better performance, but is a step towards ensuring extended system life, saving money, and potentially reducing the environmental footprint.

    Sterlitech offers 0.8 micron, 47 mm MCE filters that are suitable for use with the ASTM D7752-11 method. These versatile filters have a wide variety of applications, including contamination analysis, due to their superior flow rates, precise pores, and durable construction.

    For more information on MCE filters, please visit or contact us at To view other Sterlitech product applications in standard methods, please visit

  7. Kids Taking Center Stage in Science Awards

    Kids Taking Center Stage in Science Awards

    Leave it to Google to shine a light on our next generation of young scientists!  As we start getting ready for the 2017 academic year, Sterlitech decided to look back at last year’s Google Science Fair awards.  One group of clever kids caught our attention by winning the 2016 Scientific American Innovator Award with a subject near and dear to our hearts: filtration. They made filters from a unique source – waste Styrofoam packing! 

    The trio of middle school students from Columbus, Ohio, came up with the idea after one of the three made a trip to Central America the prior year.  The student was surprised at the volume of Styrofoam trash that littered the beaches and wondered if there was something that could be done.  Further research into the use of Styrofoam in the United States showed an estimated 25% of our landfill waste space is occupied by Styrofoam packing alone– close to 1.9 Billion pounds!

    The Ohio eighth-graders (Ashton Cofer, Luke Cray, and Julia Bray) decided to put their heads together and enlist the help of scientists from Battelle Memorial Institute and the Ohio State University to determine if the Styrofoam could be easily converted from a waste product into a useable product.  Since Styrofoam is mostly carbon, they asked, “What usable things can be made from carbon?”.  The simple and easy answers are graphite, diamonds, and activated carbon.  Activated carbon is a common raw material used in air and water filtration systems as it does a very good job of absorbing pollutants and contaminants.  So why not start there?

    Styrofoam is a type of expanded polystyrene, its polymer chains composed of over 92% carbon.   The current process of recycling Styrofoam into new packing material typically results in carryover of impurities.  These impurities often make the finished product more expensive and undesirable when compared to new Styrofoam.  The trio of students, and their mentors, discussed the problem at length and came up with an experimental process to convert the waste Styrofoam into activated carbon.   They revised the conversion process several times to optimize the activated carbon format and then tested the activated carbon against common water pollutants such as iron, copper, and chlorine.  All their hard work yield ultimately yielded positive results!   Their newly made Styro-Filter material reduced iron by 98%, reduced copper by 90%, and chlorine by 20%.  These results are comparable to conventional  activated carbon already employed in water filtration. Good job kids!

    Sterlitech congratulates Ashton, Luke, and Julia for their hard work and resourcefulness at tackling a significant waste problem and turning it into a useful technology.  We’re looking forward to this year’s entrants in the 2017 competition!

  8. Simplify and Centralize Your Purchasing: PunchOut Catalogs Now Available from Sterlitech

    Simplify and Centralize Your Purchasing: PunchOut Catalogs Now Available from Sterlitech

    Ariba, Coupa, SciQuest/Jaegger, and Oracle are just a handful of the increasingly popular purchasing platforms that enable subscribers to streamline purchasing processes between customers and vendors. These platforms often offer seamless integration into enterprise resource planning (ERP) systems, allowing for increased product visibility, expedient order processing, and timely invoicing. Part of this rising trend includes the use of PunchOut Catalogs in these platforms for eCommerce. Through PunchOut Catalog a buyer can have access a supplier's Web site from the buyer's own procurement application.

    Purchasing from Sterlitech is easier than ever, as we are actively enabling PunchOut Catalogs for interested customers using almost any purchasing platforms. With our PunchOut Catalogs, you’ll readily and easily have access to our products while maintaining connection to your procurement system. Each PunchOut Catalog can be customized to your institution, simplifying product requisitions and ordering.

    If you have an eProcurement system that accepts PunchOut Catalogs and are interested in setting up Sterlitech’s Catalog, please contact today.

  9. Introducing: Dyed Polycarbonate Track-etch Membrane Filters

    Introducing: Dyed Polycarbonate Track-etch Membrane Filters

    Sterlitech is pleased to announce that you can now find the dyed polycarbonate membrane filters on their new product page, These hydrophilic, polycarbonate track-etch (PCTE) membrane filters have been pigmented using black dye to minimize membrane autofluorescence. The dyed PCTE membrane filters are ideal for use with fluorescence microscopy analyses that involve direct observation and enumeration of animal cells or microorganisms that have been labeled with fluorescent markers. They are also suitable for optical microscopy studies of light colored particles and microorganisms by providing a dark background for enhanced contrast.

    We now offer two types of the dyed PCTE membrane filters to cover the broadest possible range of potential applications.  One type is dyed using the traditional method with Irgalan Black dye. The resulting membrane filters appear gray in color and have varying shades depending on pore size rating. These filters have very low autofluorescence while retaining some amount of the inherent translucence of PCTE membrane filters. They are well suited for applications where both fluorescence microscopy and conventional optical microscopy may be performed on the same sample.  The translucence of the filters allows for optical microscopy using light transmitted through the membrane. To differentiate these filters from the second type, they are listed as “gray” in the product descriptions. 

    The second type of the dyed PCTE membrane filters is pigmented using a proprietary dying process. The resulting filters are dark black in appearance and have essentially no autofluorescence and almost no translucence. These filters are ideally suited not only for conventional fluorescence microscopy but also for automated fluorescence microscopy as well. Additionally, these dark black filters provide maximized contrast for optical microscopy studies of light colored particles or microorganisms. Please note that it may be possible to leach trace amounts of dye from these filters if they are used with non-aqueous solvents. These filters are listed as “black” in the product descriptions.

    Sterlitech offers a wide variety of membrane disk filters and filter holders to meet your application needs. Please feel free to contact us if you need any assistance with your selections.

  10. The Sterlitech Glass Filter funnel assembly gets an upsize!

    The Sterlitech Glass Filter funnel assembly gets an upsize!

    13mm, 25mm, 47mm, and 90mm – These were the available diameters of various glass filter funnels available suitable for use with membrane disc filters; until now.

    Sterlitech is proud to announce the launch of a new larger 150 mm diameter All-Glass Filter Assembly with a 10 liter receiver flask for processing significantly higher volumes in a single holder! Borosilicate glass filter funnels are ideal tools for use in laboratory and bench-scale filtration as they have very good chemical resistance against solvents, caustics, and most acids. When paired with the right membrane disc filter, they find a place in almost any microfiltration application area.

    The 150mm All-Glass assembly comes after a year of development work that originally centered on the filtering active compounds for cannabis applications in a process known as winterizing (cold filtering) extracts. The 90mm funnel assembly has been working hard in this area for that time, but more extraction facilities are coming on line and the need arose for a higher throughput processing design.

    The new assembly uses the same proven technology as the 90mm holders, but now has a 2 liter funnel on top, a funnel base with a PTFE-coated stainless steel membrane support screen, a GL14 port to connect to a vacuum line, and a 10 liter receiver coated with PVC to minimize risk of thermal and mechanical shock.

    Compatible with any thin-film or polymeric membrane disc filter of 150mm diameter, such as cellulose, PES, PTFE, and many more, the 150mm All-Glass assembly will be available for release in Early August 2017 for $2545.46.  Sterlitech will also offer this unit as part of a complete Botanical Extract Filter Kit that includes a vacuum pump, tubing, and 3 packs of filters for $3603.85. Contact a filtration specialist today at to learn more about this new tool for filtering liquids faster than ever!