WaterSep's HF Product Selection Guide
It takes a few easy steps to choose the optimum WaterSep hollow fiber cartridge for your crossflow application needs:
PRODUCT LINE SELECTION
Choose one of our product lines based upon your requirements and preferences, Green, Steamer, ReUse.
Choose the single use Green Line for ease of use. Gamma irradiated, glycerin free and ready to use. No membrane pre-treatment required.
The Steamer Line is our go to product for perfusion and aseptic applications. Steamer cartridges have similar properties to Green Line cartridges but can also be autoclaved and cleaned with up to 1 M NaOH.
The ReUse Line is for those applications where cleaning and re-use of cross flow membranes are acceptable. The low binding m-PES membrane enables easy and effective cleaning.
All three product lines are available in all product sizes, molecular weight cut-offs (MWCO)/pore sizes and fiber ID’s and have similar retention and flux characteristics. The membrane for all three product lines is our well accepted low binding m-PES.
FIBER ID SELECTION
Choose one of WaterSep's three different fiber ID's for your application, the 0.5 mm, 1.0 mm or 2.0 mm.
- The 0.5mm fiber ID is recommended for most concentration/diafiltration applications, where viscosity and concentration is low.
- The 1.0 mm fiber ID is for general use for both concentration and diafiltration and is your best choice for vaccine, cell harvest, and cell clarification applications.
- The 2.0 mm is our largest fiber ID and works best for applications that involve high viscosity solutions and large particle laden feed streams.
MWCO/PORE SIZE SELECTION
Choose your molecular weight cut-off (MWCO)/pore size. The general rule for achieving > 95% retention is that the macromolecule should be 5-6x larger than the MWCO of the selected membrane.
The following MWCO/pore sizes are recommended for specific applications:
|Recombinant Proteins and Enzymes:
|coli and E.coli Lysate:
||750K MWCO-0.1 um
|Whole Cell Bacteria:
Choosing which one of our eight different cartridge sizes will work best for your application is as simple as matching up your sample/batch volume or your surface area to the cartridge in the table above.
a. Sample/Batch Volume Method
- Determine what sample/batch volume you are currently using or intend to use for your application.
- Find your volume on the table above and match it up to the corresponding cartridge.
- When sample/batch volumes overlap choose a smaller cartridge to accommodate a small pump and tubing or a larger cartridge for faster processing.
b. Surface Area Method
- Determine the optimum membrane surface area for your application by using the formulae.
A = V/(FxT)
A = Membrane Surface Area
V = Sample/Batch Volume
F = Process Flux (LMH)*
T = Process Time
Your expected process time is 4 hours, your sample/batch volume is 2000L and your process flux is 30 LMH. Your membrane surface area is A.
- A = 2000 / (30 x 4)
- A = 17 m2
* Process Flux (LMH) is based on previous trials or knowledge from similar applications.
Find your surface area on the table above and match it to the corresponding cartridge.
c. Please note that all cartridge types come in 3 identical fluid path lengths (12", 24" and 41") for ease of scale up. Scale up can be achieved by increasing the length of the fiber or by increasing the number of fibers and maintaining the fiber path length.
Once you have determined the WaterSep cartridge that meets your exact specifications you may need to determine your crossflow requirements. The chart below will help you determine your crossflow requirements based on the fiber id and size of the cartridge that you have selected.
Note: For higher sheer multiply the above crossflow requirements by a factor of 1.5. For very high sheer, such as E. Coli processing, multiply by a factor of 2.0.
If you need assistance in finding the right cartridge or assembly for your exact needs, kindly contact us at Experttalk@watersep.net. We are committed to providing you with the optimum product for your application.
For a more in-depth review of WaterSep’s HF products please see our:
Home Page: Green, Steamer and ReUse Lines, and
Technology Page: Technology Overview and Hollow Fiber Membranes.