Molecular Weight Cutoff (MWCO) of a membrane is an indirect
measure of the molecular size of the compound that has a specific
percent retention. The standard unit of measure for MWCO is
one Dalton, the size of one hydrogen atom. Since MWCO is a
measure of size, there is no direct conversion to a metric pore
diameter. A convenient chart that relates sizes compared with
MWCO is provided in our book, The ABCs of Filtration and
Bioprocessing for the Third Millennium. Call us to receive your
free copy or request online at www.spectrumlabs.com.
Since the membrane porosity does not interfere with the diffusion
of nutrients and waste, the pore size is only taken into consideration
when determining whether you want secreted product confined
to the extracapillary space (ECS) or passing into the media
supply. Below are some guidelines you can use to choose a cartridge
that will work best for your application.
Adherent cells for collection of secreted products: Use the
Regenerated Cellulose (RC) or Polysulfone (PS) membranes. Seed the cells
in the ECS. The large surface area will allow you to grow a large
number of cells in a small space. The small pore sizes will allow
you to collect and concentrate your secreted products in the
extracapillary space (ECS).
Adherent cells for shear stress: Use the coated polypropylene (PP) or
polyethylene (PE) cartridges for shear stress assays. The large lumen
allows you to seed the cells onto the inner capillary surface (inner
side of the fiber) and to measure effects of media flow on the
adherent cells.
Adherent cells for collection of non-secreted products: Any cartridge
will work. If you desire a large number of cells, choose a
cartridge that has a high surface area.
Suspension cells: Any suspension cell line should be seeded in
the ECS. Use the RC or PS membranes.
If you are not collecting product, you can use the
PP or PE membranes.
Spectrum offers a variety of hollow fibers for all of your cell culture needs. Not sure which to choose? Here is a quick summary.
| Fiber | Properties | Pore Size/MWCO | Use |
| Regenerated Cellulose (RC) | Hydrophilic; Cells bind strongly; resistant to organic solvents | 30 kD | Adherent cell lines and hybridomas |
| Polypropylene (PP) | Hydrophobic; cells bind poorly; can be coated to enhance cell attachment | 0.5 µm | Large diameter fibers can be used for shear stress studies |
| Polyethylene (PE) | Hydrophobic; cells bind moderately; Can be coated to enhance cell attachment | 0.3 µm | Large diameter fibers can be used for shear stress studies |
| Polysulfone (PS) | Hydrophobic; cells bind strongly over time; resistant to organic solvents | 30 kD, 100 kD | Higher flux than RC fibers. Use similar to RC fibers |
Ordering Information: Artificial Capillary Module w/ Flow Path
|
| Part No. | Membrane
Type |
95%
Retention | ECS (ml) |
Fiber Dimensions | Price |
Outer Surface
Area (cm2) | ID (µm) | OD (µm) |
| 410-011 | RC | 35 kD | 10 | 2000 | 200 | 216 | $387 |
| 400-004 | RC | 20 kD | 100 | 16000 | 192 | 200 | $561 |
| 410-010 | PS | 10 kD | 10 | 2000 | 200 | 216 | $387 |
| 400-025 | PP | .5 M | 1.5 | 100 | 480 | 630 | $155 |
| 410-025 | PP coated | .5 M | 1.5 | 100 | 480 | 630 | $168 |
| 400-014 | PE | 0.3 | 2.3 | 123 | 380 | 430 | $354 |
| 400-012 | PE | 0.3 | 12 | 1500 | 380 | 430 | $387 |
Ordering Information: CellMax Accessories
|
| Part No. | Description | Includes | Price |
| 100-145 | CellMax Starter Kit | Supplies for maintaining and harvest art. capillary modules | $63 |
| 100-020 | Reservoir Cap, 33 mm | Polysulfone cap w/ tubing for 500 ml & 1 L glass bottles | $124 |
| 100-025 | Reservoir Cap, 38 mm | Polysulfone cap w/ tubing for 500 ml & 1 L square plastic bottle | $124 |
| 010-006 | Replac. Flow Path | Ready-to-Use standard flowpath for art. capillary module < 1 m2 | $100 |
| 010-007 | Replac. Flow Path | Ready-to-Use flowpath for increased oxygenation for art. capillary module > 1 m2 | $124 |
| 
